Improve perf of createAlternanteImpl

- Creates return-type specific return functions that are determined at
  creation time.
- Splits off promise handling to it's own function. Overrides that use promises
  must indicate so when creating the override with the usesPromise param.
- Updates overrides that use promises
Merge pull request #536 from EricRahm/alt_impl_perf

Improve perf of createAlternanteImpl
Implement ImageDataFactory::createImmutableImageDataRegion native. Fixes #541.
Remove WIP comment
Set mutable field in the destination ImageData object
Ignore spurious mousemove events.
Add test that creates an image from a region of another one
Print "FAIL" when failing to load the image, so the casperjs script can catch the failure
Merge pull request #542 from marco-c/createImmutableImageDataRegion

Implement ImageDataFactory::createImmutableImageDataRegion native
Merge pull request #543 from mcav/mousemove

Ignore spurious mousemove events.
Merge branch 'master' of https://github.com/andreasgal/j2me.js into nokia_image_processing_test

Conflicts:
	tests/automation.js
Increase number of maxDifferent pixels to pass on Mac
Replace list of files to be included in the JAR with a Makefile variable