Created Sessions controller

This will be used for authentication for signin and signout.

Intention is :
GET => /signin	=> signin_path => new => page for a new session (signin)
POST => /sessions => sessions_path => create => 	create a new session
DELETE => /signout => signout_path => destroy => delete a session (sign out)

Signed-off-by: Ippoippo <ippoippo-software@ippoippo-eco.com>