Removed PlatformUtil.saveProto() method, as it was a unnecessary abstraction that served no benefit.
Open container selection dialog
Add dispose listener. When disposed, notify LayersViewPart to act accordingly.
Add some editing features like key navigation and tab editing.

http://git.eclipse.org/c/platform/eclipse.platform.ui.git/tree/examples/
org.eclipse.jface.snippets/Eclipse%20JFace%20Snippets/org/eclipse/jface/
snippets/viewers/Snippet025TabEditing.java
Open Container Selection Dialog
Case for background and entity shapes for importing contents from another screen.
NA
Removed
Refactor PlatformUtil to ScrenEditorUtil
Refactor PlatformUtil to ScreenEditor Util
Refactor PlatformUtil to ScreenEditor Util
Refactor PlatformUtil to ScreenEditor Util
Minor refactor
Open Container Selection Dialog
Removed the use of PlatformUtil.saveProto
Removed the use of PlatformUtil.saveProto
While making shape, check if the type is entity and set the correct values.
unnecessary constatn STRING_EMPTY
add createImage() method
Refactor into ScreenEditorUtil