Merge pull request #2 from EmilWestergren/master

Added general image open function in RasterImage for loading image with unknown format
Added tests converting from monochrome to bgr and bgra - which doesn't work.
Fixed broken conversion from Monochrome.
Implement IDisposable using empty functions.
Fixes #3
Added shifted image for tests.
Merge branch 'master' of https://github.com/cogneco/ooc-draw
Merge pull request #4 from EmilWestergren/master

Added channelOffset for UV channel in Yuv420Semiplanar
Fixed performance bug.
Merged.
Merge branch 'master' of https://github.com/cogneco/ooc-draw

Conflicts:
	ooc-draw.use
Added Open function to 420Semiplanar.
Added binary load and save in Semiplanar, and related tests.
Added dispose fuction.
Tried to fix memory leaks.
Fixed merge
Fixed __destroy__ in some of the image classes.
Removed IDisposable.
Fixed return type in copy function in image classes.
Fixed __destroy__ in RasterYuv420Semiplanar