[jaiguru] report-folder patch

This patch contains:
* inbuilt "reports" folder is now checked and all subfolders containing a main.jrxml file are added to the report list (using folder name as report name)
* same mecanism is used for USER_DATA_FOLDER/reports (so no new preference needed)
* my customizable report is added to the inbuilt "reports" folder

Remarks:
* I didn't created a configurable preference for that, but I think the best would be to have such configuration option with default value if unset being USER_DATA_FOLDER/reports. This would allow team members to use same reports without having to copy them locally (network shared folder could be used instead).
* I've added my report but the default background should be changed to match the new Archi style. I'm sure you'll have good idea for it.
* I now have to create a model template for this report.

Regards

Jaiguru