end application when TestChooser dialog is closed

added a WindowListener in the constructor that overrides the windowsClosing method to dispose the TestChooser dialog. 
code tested with positive result for issue#85.
issue#85 short approach - setDefaultCloseOperation
TerrainLodControl no longer caches camera positions. Issue #121
set buildNativeProjects to false for now
Added base input handler - touch and simulated mouse
Merge pull request #117 from maany/issue#85

Issue#85 fix from maany
Update CONTRIBUTING.md

many updates. basic tips about github use, bug reporting and code style.
Fixed issue in MotionPath where having a path with only 2 waypoints with the same coordinates was causing an IndexArrayOutOfBound exception.
Also used a temp var for a Vec2 that was instanciated on each frame
Merge branch 'master' of https://github.com/jMonkeyEngine/jmonkeyengine.git