t_tune for oggvorbis.
hacked INSTALL.md
Hacked README.md
Cleaned t_ftflac
change the "backend" action output format in order to allow simpler parsing.
Added a optionnal setup routine to backends.
Improved libid.
Removed backend setup (should be in t_ft<lib>_backend() routine). Removed the possibility to override the backend priority.
Remove unused variables.
Commit a version of t_ftgeneric.c that make clang crash.

FreeBSD clang version 3.1 (branches/release_31 156863) 20120523
Target: x86_64-unknown-freebsd9.0
Thread model: posix
Working TagLib backend with t_tune.
Fix write return value in ogg/vorbis backend
t_file cleanup.