Update buildtools to version 1.0.14-prerelease
Merge pull request #182 from FiveTimesTheFun/buildtools-14

Update buildtools to version 1.0.14-prerelease
Remove AllowUnsafeBlocks as it's no longer needed
Make immutable collection tests portable
Remove commented out code (responding to PR feedback)
Merge pull request #183 from nguerrera/portable-immutable-tests

Make immutable collection tests portable