add timer
inc planes' speed
Merge branch 'gh-pages'
refactoring: move entities to separated source
refactoring
add pause screen
add stubs for screens
add ui
refactoring
minor
minor
refactoring
add input
add input
fix input
fix input
add menu
ad base ui
add menu
ad base ui
refactoring
new explosion animations
timers
etc
refactoring
add base layout
add more states
add menu
ad base ui
scaling