Add support for general GModelData simulations.

Background simulations can now be done for any model of type GModelData. This is thanks to the abstract mc() method that has been introduced in GModelData. A test case for the new GCTABackground model has been added to the unit tests.
Fix all parameters for the moment.
Add some unit tests
Fit prefactor and index.
Removed debugging sleep instruction
Adapt to new GCTARoi and GCTAInstDir interface.

The GCTARoi::contains() method is now used to check for ROI containment.
Add testing of diffuse map cubes to Python unit test.
Add PHA spectrum display script.
added energy binning options 'FILE' and 'LIN'
Code revision before merging and updated ctbin version number and change information.
Merge branch 'integration' into devel
Avoid constructor in constructor as this apparently leads to problems on older gcc compilers.
Merge branch 'integration' into devel
Longitude in skymaps and counts maps now increases towards the left. Only relevant projections are proposed in parameter file.
Add "AIT" projection to possible projections.

The AIT projection is now available in GammaLib.
Adapt to new GSkymap interface.
Add logfile parameter.

The hidden logfile parameter allows specifying the name of the logfile.
Unit test do no longer delete log files.

Deleting log files led to a problem with the new automake test suite.
Adapt to new FITS interface
Adapt to revised GammaLib interface.