Tests: Added Tests+Benchmarks for Mappers
SlicerTests: Updated format and documentation
SlicerTests: Updated format
AbstractOpTest: Added function to generate images
ThreadedMappers: Fixed bugs with chunkSize
Merge branch 'master' of https://github.com/imagej/imagej-ops

Conflicts:
	src/test/java/imagej/ops/tests/SlicerTests.java