Add the LIRMM certificat

The LIRMM certificat is needed to access the Git/Mercurial repositories host by
LIRMM.
Add a 'gls' alias

'gls' is an abbreviated alias for 'git ls' which is an alias for 'git ls-files
-v --cached'.
Add the verbose mode for 'tunnel-bison'

Need the verbose mode to know which state is the connection.
Improve terminal's fitting with Vim

If the terminal is 'rxvt-unicode', adapt the mouse interactions with the
well-fitting option.