This patch adds support for various mount options.  It is also able to pass extra 
mount option data to mount(2).  For example, it allows users to mount aufs file 
system at lxc_start time.

See the thread
	http://sourceforge.net/mailarchive/forum.php?thread_name=E6D98D6C-F633-419A-9424-F24EBB3E11D9%40aist.go.jp&forum_name=lxc-devel
for details.
Signed-off-by: Ryousei Takano <takano-ryousei@aist.go.jp>
Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>