Save working

Summary:
	-Now it save both images on the tests/results folder on the project. Also minor modification on the gitifnore for not push them.
	-Average per band implemented on the ImageUtils lib.
Feature complete

Summary:
	-Style modified to manage left and right image.
	-Abstract classes created for the above point.
	-Avg is now showing when you create a subimage, also amount of pixels.
	-New menu to save images on the external frames of histograms.