level2+level3+divider_half+divider_third

level2: obstacle
level3: divider (half), two exits, only accepts half volume of the light
beam
Merge remote-tracking branch 'origin/master'

Conflicts:
	Assets/Level1Scene.unity
updated scene 2&3

fix missing material and assets
Revert "updated scene 2&3"

This reverts commit 948328eff11c740a08ccb3bb15aa48e8b9668fb4.
Revert "level2+level3+divider_half+divider_third"

This reverts commit d3ed16404994937882621d50308c5a0f1185f228.
Merge branch 'master' of https://github.com/foxking0416/re-frARction