Add a section for clang to doc/make/ccache.md
Update ccache.md

fix typo [skip ci]
Update ccache.md

Add reference [skip ci]
Update todo.md
Update todo.md
Update doxygen process, only update changed files
Update binary uploading process

- fix commit name for OSX & Windows
- fix NOW to use specific time zone, PST
- upload compressed binary for archiving
Attempt to suppress valgrind warnings on Travis

- don't understand why cmake on travis doesn't pick up the memcheck.supp
file. It works on my local machine.