Add CI builds for Carthage and CocoaPods

[mattrubin]

Add CI jobs which try building the library with Carthage and CocoaPods, on both Xcode 9 and 10.

Currently, CocoaPods' pod lib lint command has a bug with the preserve_paths configuration used to provide custom CommonCrypto modulemaps on Xcode 9.x. Until that bug is fixed, the Xcode 9 CocoaPods CI job is allowed to fail.

[codecov]

Codecov Report

Merging #192 into develop will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #192   +/-   ##
========================================
  Coverage    97.22%   97.22%           
========================================
  Files            6        6           
  Lines          397      397           
========================================
  Hits           386      386           
  Misses          11       11

---

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Δ = absolute <relative> (impact), ø = not affected, ? = missing data
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[codecov]

Codecov Report

Merging #192 into develop will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #192   +/-   ##
========================================
  Coverage    97.22%   97.22%           
========================================
  Files            6        6           
  Lines          397      397           
========================================
  Hits           386      386           
  Misses          11       11

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 785861e...2f92239. Read the comment docs.

[codecov]

Codecov Report

Merging #192 into develop will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #192   +/-   ##
========================================
  Coverage    97.22%   97.22%           
========================================
  Files            6        6           
  Lines          397      397           
========================================
  Hits           386      386           
  Misses          11       11

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 785861e...2f92239. Read the comment docs.

[codecov]

Codecov Report

Merging #192 into develop will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #192   +/-   ##
========================================
  Coverage    97.22%   97.22%           
========================================
  Files            6        6           
  Lines          397      397           
========================================
  Hits           386      386           
  Misses          11       11

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 785861e...2f92239. Read the comment docs.

[codecov]

Codecov Report

Merging #192 into develop will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #192   +/-   ##
========================================
  Coverage    97.22%   97.22%           
========================================
  Files            6        6           
  Lines          397      397           
========================================
  Hits           386      386           
  Misses          11       11

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 785861e...2f92239. Read the comment docs.

[codecov]

Codecov Report

Merging #192 into develop will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #192   +/-   ##
========================================
  Coverage    97.22%   97.22%           
========================================
  Files            6        6           
  Lines          397      397           
========================================
  Hits           386      386           
  Misses          11       11

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 785861e...2f92239. Read the comment docs.

[codecov]

Codecov Report

Merging #192 into develop will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #192   +/-   ##
========================================
  Coverage    97.22%   97.22%           
========================================
  Files            6        6           
  Lines          397      397           
========================================
  Hits           386      386           
  Misses          11       11

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 785861e...2f92239. Read the comment docs.

[codecov]

Codecov Report

Merging #192 into develop will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #192   +/-   ##
========================================
  Coverage    97.22%   97.22%           
========================================
  Files            6        6           
  Lines          397      397           
========================================
  Hits           386      386           
  Misses          11       11

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 785861e...2f92239. Read the comment docs.