.gitignore : simplify + ignore private
Revert ".gitignore : simplify + ignore private"

This reverts commit 0e5e58a1f87dd6f2feea6cc1366c681129b55358.
gitignore: add explicit list of private files to ignore
gitignore: ignore directory instead of files
Merge pull request #142 from davidB/wip_sdk_properties_control

SDK: fix JmeGenericControl to display initial value of Property and inhe...
Merge pull request #141 from davidB/wip_scenecomposer

.gitignore : simplify + ignore private
SDK: fix NPE in JmeGeometry.propertyChange
Merge pull request #143 from davidB/fix_npe

SDK: fix NPE in JmeGeometry.propertyChange
 * Deprecated LTC and LATC texture formats, OpenGL3+ does not support them. Instead RGTC / BC5 must be used.
 * Add missing license to InstancedGeometry.
 * Minor cosmetic / doc changes.
Merge branch 'master' of github.com:jMonkeyEngine/jmonkeyengine
 * ToneMap.frag: Fix warning about gl_FragColor when compiling for GLSL 1.5 and higher
 * Added two missing 32-bit image formats to TestImageRaster: ARGB8 and BGRA8
* When creating display pixel format, do not use withSRGB as it could cause display creation to fail (when gamma correction is enabled). Based on online research, it seems that it is not necessary, and simply enabling SRGB writes on the main framebuffer is enough.
 * Added additional checks when enabling SRGB writes to ensure the default framebuffer actually supports it, and print a warning if it doesn't.
 * Forgot to remove withSRGB from LwjglCanvas
Merge origin/master
Merge branch 'master' into wip_sdk_scenecomposer
Spatial remove "null" from controls on read(...). 
It's possible if the class of the control is not found (may be deleted).

In SDK with this modification, the exception about ClassNotFound is "notify" 
but it no longer raise a NPE (on clone()) and the j3o can be open and edited
without the missing Control.
SDK / SceneComposer : change physics buttons
- merge play an pause Physics buttons in a singleToggleButton
- add a debug ToggleButton to display physics body
SDK: can create primitives geometries (Box, Sphere) in SceneExplorer
SDK: add action to Quad, Line geometries  in SceneExplorer and a NewGeometrySettingsTopComponent to configure the creation.