* Reworked Processor object.
* optimized the number of thread used by the application (limited on
win32 JVM).
* added ThreadUtil.runSingle(..) to run a single instance of a process
(same as the previous bgRunSingle()).
* SequenceUtil.scale(..) now correctly update pixel size information.
* fixed XLSUtil error message.
* cleanup
minors changes.
* reverted some changes with thread optimization (don't optimize too
much ^^).
* others minors fixes