add Map Element: Sand
Merge branch 'master' into fntsrlike

Conflicts:
	game/scene/scene_game.lua
Update CREDIT
Add tutorial images
Merge branch 'master' of github.com:raincole/isr
Let speed value set on metadata and remove console msg
remove all of test massege on screen
Merge branch 'master' of https://github.com/raincole/isr
Merge branch 'master' of github.com:raincole/isr
Update CREDIT
Implement tutorial