recovers branch selector for backend
Adds Menu object

adds menus to branches
automatically creates a menu for each branch
fixes serveral redirect issues in menus controller
Merge branch 'dev' of github.com:farfanoide/agalma into dev
refactor backend menus variables
nicer view on menus index

also refactors some old code on _mod's
destroy model direccion, page belong branch, page add branch_menu automatically
adds drop directions migration
removes sidebar menu
adds menus

adds views for menu's crud
adds general scope in pages
minor changes to menu forms