Merge pull request #27 from lat-lon/dragAndDropLayertree-191

Drag and drop layertree 191
Implemented layer aggregation in printing module. Disabled vector layer rendering.
Merge branch 'latlon-version' of github.com:lat-lon/geomajas into printingTimeoutFix
Fixed build error in printing module color correction
Refactored raster layer aggregation in printing component and mapmodel
Merge pull request #29 from lat-lon/printingTimeoutFix

Printing timeout fix
Merge pull request #30 from lat-lon/latlon-version

Merge latlon-version in dragAndDropLayertree