Libiconv 1.14

Throwing this out here to get the ball rolling on review.

- Bump libiconv to the latest 1.14.
- Also bumps internal gperf to 3.0.4
- Patch was cleaned up to apply cleanly.  First part of lib/encodings.def patch was removed to prevent a collision between two encodings given the same UTF8 name.  Everything else is cosmetic.
- Fixed the addition of the compiler wrapper so that clang would be used (vs gcc)

This is 10.7 only.  But there's no foreseeable reason the same can't be applied to 10.5/6, but with the necessary changes to the compiler wrapper there.  Don't have access to 10.5/6 machines to test bootstrapping, so haven't officially done the test.