Refactored to bring out constants in ImageResource (only).
PanZoomWidget & ImageControls partially refactored due to sharing of constants, but are still pending)
Refactored ImageControls (shifted functions to private).
Fixed bug in ImageResource. newFilterMenuValues needed to be assigned an empty array to avoid "NullPointer" error
Added in tooltips even for the "lighter" buttons.
Refactored ImageControls (extracted magic constants).
Minor refactor for ImageResource.
Adding ImageResourceViewer unit test stub.
Need to merge with master for the most up-to-date libraries.
Merge pull request #138 from blackhydrogen/resource-image

Resource image