added tests for image decomposer
added sl4j dependencies
added maven compiler plugin
added guava dependencies
added image decomposer:
accepts as input some image and outputs
three bufferedImages, each bufferedImage
is the C/M/Yscale representation of the
original image.
added tests for ColorDecomposer.
changed getIntFromcolor to public method.
Merge pull request #2 from cIrinel/prepare-image-for-halftoneing

Prepare image for halftoneing