Cleaning
Specify number of rendering engine.
Initial work to start several re per image.
Fix tile loading issue.
Add number of re to start to configuration file.
Only initialize one RE for a non large image.
Remove System.err.println()
Add logic to reset/reload methods (see #7918)
Merge pull request #938 from jburel/rebased/develop/big-image-rnd

Big image rnd (rebased onto develop)