Summary:
`make clean` would fail calling `xcodebuild` to clean. It also calls `ant
clean`. Instead, do the cleaning ourselves by deleting the appropriate stuff so
that it's faster and more reliable.
Also clean the OCaml build before cleaning the tests as that's what more
important most of the time.
Also don't delete the man pages as part of `make clean` as they are checked in.
Also fix ant's Makefile so that the build points at the right .class files (the
path to the .class files was wrong so `make -C infer/tests/build_systems/ant`
would start `ant` for *each* file instead of once).
Reviewed By: martintrojer
Differential Revision: D13956218
fbshipit-source-id: bce27fe11