Pets: Detailed errors

[Oliver]

Detailed errors with pets.

room.error.pets.forbidden_in_flat=Sorry, pets are forbidden in this room.
room.error.pets.forbidden_in_hotel=Sorry, pets are forbidden in this Hotel.
room.error.pets.no_free_tiles=The space in front of you is not empty. Please move to another spot and try placing your pet again.
room.error.pets.respectfailed=You can scratch other users pets once your account is %required_age% days old. Your account is now %avatar_age% days old.
room.error.pets.selected_tile_not_free=You can not place your pet there, pick another tile.

[Wesley]

Most of these were already implemented. Added the no_free_tiles one.

[Wesley]

Removing version: 1.11.0 (automated comment)