Fix broadcast for 0.5

[davidagold]

This PR transitions the NullableArrays broadcast interface to incorporate that present in base: https://github.com/JuliaLang/julia/blob/913b24de9c68b6c79a767bc2f6caacea249b3198/base/broadcast.jl. Functionality remains the same. I made one minor revision to the tests, which originally checked (for some reason) that broadcast! and map! give identical behavior when fed only a single array argument. They don't -- see JuliaLang/julia#12277. The fact that those tests were ever not problematic means that the semantics of broadcast specialized for NullableArray arguments were not consistent with those in base. Now they are.

[quinnj]

Hmmm, looks like this breaks 0.4. We also still have a few other fixes needed for 0.5 (which is why that check failed).

[coveralls]

Coverage decreased (-12.07%) to 66.22% when pulling 05e1bf0 on broadcast into 1616e96 on master.

[davidagold]

The push failed because I hadn't pulled Milan's fixes for the other stuff. The PR failed because I forgot I couldn't just nix all the old definitions >_> Fixing that now.

[codecov-io]

Current coverage is 82.96%

Merging #123 into master will increase coverage by 4.67%

@@             master       #123   diff @@
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  Files            13         13          
  Lines           677        716    +39   
  Methods           0          0          
  Messages          0          0          
  Branches          0          0          
==========================================
+ Hits            530        594    +64   
+ Misses          147        122    -25   
  Partials          0          0          

Powered by Codecov. Last updated by 1616e96...77de5a9

[coveralls]

Coverage increased (+4.7%) to 82.961% when pulling 87af2ae on broadcast into 1616e96 on master.

[davidagold]

"Rebasing" this in a crude yet (hopefully effective) manner.

[coveralls]

Coverage increased (+4.7%) to 82.961% when pulling 77de5a9 on broadcast into 1616e96 on master.

[davidagold]

Comments/suggestions @quinnj @nalimilan ?

[nalimilan]

Cut line at 92 chars.

[nalimilan]

Cool. I could only make superficial comments. Please merge and tag a new release as soon as you can!

[quinnj]

Travis is happy :)

[coveralls]

Coverage increased (+4.9%) to 83.148% when pulling 4dec5b9 on broadcast into 1616e96 on master.

[davidagold]

@quinnj @nalimilan I don't know what to make of the push failure. I can't recreate it locally. Possibly just some floating point weirdness? Though I don't see how that would be possible...

EDIT: It's especially weird, since the push and pr versions should be identical.

[quinnj]

I restarted the build. I'll also pull locally to see if I can reproduce.

[quinnj]

Must have been intermittent; it all looks good now.

[quinnj]

Hmmm.....any idea what the map failure is, @davidagold? https://travis-ci.org/JuliaStats/NullableArrays.jl/jobs/139840111

[davidagold]

... No? When did that happen?

Edit: master seems fine locally...