Added Emgu CV submodule
Implemented Palette and NCLR file format with new engine
Changed color type to RGBA and depth to Byte
Implemented Image with new engine
Improved perfomance creating palette images
Moved color static methods to color extensions
Implemented Map, NPCK file format and Import with new engine.

* ColorExtension.cs: Temporaly fix in Rgba constructor while it's
  fixed in Emgu.CV

* Importer.cs, Map.cs, Npck.cs: Implemented with new engine

* Program.cs: Better way to calculate elapsed time

* Tests.cs: Updated with new engine
Resolved problem with hint paths