Add CustomReflectable implementation to most Foundation value types.

[parkera]

What's in this pull request?

Adds CustomReflectable implementation to most Foundation value types.

Also improves the basic debugDescription and description methods.

Resolved bug number

rdar://26580762

---

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[parkera]

@swift-ci Please test and merge

[parkera]

<unknown>:0: error: could not acquire lock file for module 'Darwin': failed to create link /var/folders/_8/79jmzf2142z2xydc_01btlx00000gn/C/org.llvm.clang.buildnode/ModuleCache/1SZRYF7WWU99E/Darwin-HUB66TE1ZK5G.pcm.lock to /var/folders/_8/79jmzf2142z2xydc_01btlx00000gn/C/org.llvm.clang.buildnode/ModuleCache/1SZRYF7WWU99E/Darwin-HUB66TE1ZK5G.pcm.lock-b0ff6f2d: No such file or directory
/Users/buildnode/jenkins/workspace/swift-PR-osx/swiftpm/Sources/PackageDescription/Package.swift:14:8: error: no such module 'Darwin.C'
import Darwin.C
       ^
<unknown>:0: error: build had 1 command failures

@shahmishal some kind of config problem? (https://ci.swift.org/job/swift-PR-osx/2762/)

[parkera]

@swift-ci Please test and merge

[parkera]

Transient I guess.

[michael-lehew]

Thanks for getting these in, hope my WIP was marginally helpful, these LGTM.

[exalted]

@parkera curious to ask: formerly NSData used to return "<xxxxxx xxxxxx ...>" when .description was called.

Now, instead, "<#bytes> bytes" returned. Was this a conscious decision please? Thanks. 🙇

[parkera]

The idea here was to print out the contents when less than a certain size (64) and otherwise just the count. If I messed something up there (totally possible) then I welcome a PR to fix it.

[exalted]

It's no biggie to me. I've just bumped into this, when I was using .description on device token when remote notifications are registered in an iOS device for years and I was surprised to see the output changed all the sudden... that's all.

Btw, I don't see the check for 64 bytes... just so you know.

Thanks!