Add Brightness, Contrast, Saturation and Vignette filters. Add components to get preset curves and apply them
Update ComponentLoader.load cb
Add writePNG to testutils, handy to debug image processing steps
Silence FindFeatureFreeAreas
Fix Brightness, Contrast, Saturation, Vignette and Adj. curve filters
Add a getCanvasWithImage function that doesnt shifts the given image
Add tests to Brightness, Contrast, Saturation, Vignette and Adj. curve components.
Add threshold check to components comparing expected PNG files.
Merge pull request #6 from automata/master

Add Brightness, Contrast, Saturation, Vignette, GetPresetCurve and ApplyPresetCurve