src/poky:go-dep: Update 0.4.1 -> 0.5.0

NEW FEATURES:

- Add CI tests against go1.10. Drop support for go1.8. (#1620).
- Added install.sh script. (#1533).
- List out of date projects in dep status (#1553).
- Enabled opt-in persistent caching via DEPCACHEAGE env var. (#1711).
- Allow DEPPROJECTROOT environment variable to supersede GOPATH
  deduction and explicitly set the current project's root (#1883).
- dep ensure now explains what changes to the code or Gopkg.toml have
  induced solving (#1912).
- Hash digests of vendor contents are now stored in Gopkg.lock, and
  the contents of vendor are only rewritten on change or hash
  mismatch (#1912).
- Added support for ppc64/ppc64le.
- New subcommand dep check quickly reports if imports, Gopkg.toml,
  Gopkg.lock, and vendor are out of sync (#1932).

BUG FIXES:

- Excise certain git-related environment variables. (#1872)

IMPROVEMENTS:

- Add template operations support in dep status template output (#1549).
- Reduce network access by trusting local source information and only
  pulling from upstream when necessary (#1250).
- Update our dependency on Masterminds/semver to follow upstream again
  now that Masterminds/semver#67 is merged(#1792).
- inputs-digest was removed from Gopkg.lock (#1912).
- Hash digests of vendor contents are now stored in Gopkg.lock, and
  the contents of vendor are only rewritten on change or hash
  mismatch (#1912).
- Don't exclude Godeps folder (#1822).
- Add project-package relationship graph support in graphviz (#1588).
- Limit concurrency of dep status to avoid hitting open file
  limits (#1923).

(From OE-Core rev: 165da89292f81d236e4e8e652500b8879c2ad9be)

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>