Pattern Editor: Selecting new pattern while editing shapes should warn user of losing edits

[landonreed]

If a user is actively editing a pattern shape, selecting a new pattern (or new route or new GTFS table to edit), should throw a window.confirm at the user to make sure they want to navigate away. I also noticed a strange behavior where the editGeometry boolean is not reset to false (the default state) when a new entity is selected (which dispatches the action type SETTING_ACTIVE_GTFS_ENTITY).