Second world part was added
Elevation added
Sand created, MapEdge added
Stashed items; sprite holder mover to another class
Preparation for a commit
Merge remote-tracking branch 'origin/planetModel'

Conflicts:
	core/src/ru/vsu/csf/twopeoplestudios/SpaceStranded.java
	core/src/ru/vsu/csf/twopeoplestudios/screens/MapTestScreen.java
Merged with PlanetModel; minor bug fixed; sand tile added