Revparse does not handle refspecs
Don't expose git_hash_ctx since it's internal

And doing so makes the mingw build choke.
travis: exit on failure for anything related to building
Merge pull request #1797 from ethomson/keep_hash_ctx_private

Don't expose git_hash_ctx since it's internal
Use time(2) to get the time

We didn't use the added precision in gettimeofday, so remove it.
This prevents us from having an unnecessary reimplementation on
win32.
Merge pull request #1799 from ethomson/gettimeofday

Use time(2) to get the time
Fix p_inet_pton on windows

p_inet_pton on Windows should set errno properly for callers.
Rewrite p_inet_pton to handle error cases correctly and add
test cases to exercise this function.
Merge pull request #1796 from ethomson/fix_inet_pton

Fix p_inet_pton on windows
Quiet down some warnings
Merge pull request #1800 from ethomson/mingw_warnings

Quiet down some warnings