Add a basic file selector with extension filtering support
Fix hard crash on hitting an out of range key (Q~P)
Add editor object to object snapping
Fix missing HeadlessTest specification in new test
Avoid destroying editor screens when changing between modes
Fix rulesets disposing game-wide texture store
Add ability to toggle editor toggles using keyboard shortcuts (Q~P)
Fix editor not showing sign when time goes negative
Fix score panel being incorrectly vertically aligned on screen resize