[travis] Don't build java wrapping with gcc.
[travis] Fix bug that was creating an extra build.
[travis] Disable python wrapping for java.
[travis] Use fewer processes for GCC.
[travis] Show make install output for debugging.
[travis] Enable wrapping again.
[travis] Only test python wrapping on clang.
Merge pull request #177 from opensim-org/travis_no_java_on_g

[travis] Don't build java wrapping with gcc.