[#42720979] Add Chat model
Fix spec
[#42720979] Add ArrivesController
[#42720979][#42848685][#42848683] Add basic chat feature
[#42848753] Change ArrivesController name
Add /rooms route
[#42848797] Add users.color column
[#42848797] Add User::Guest model
[#42848797] Use user's name & color from session
[#42848797] Set default user's name & color from session
[#42848797] Change redirect path after leave
[#42848797] Fix spec
[#42848797] Update long session
Merge branch 'chat'
Remove login menu
[#42849409] Update room's last arrived_at & left_at