Add consturctor to convert pointer types
Added *= and /= operators and friend function sqrt()
Use sphinxcontrib-doxylink to link user manual to API docs
Add data filter to binned analysis.

Event cube bins with a negative number of counts are excluded from the binned likelihood computation. This allows filtering of event bins.
Correctly propagate logfile name change. Now, before each access to the logfile name then filename is extracted from the parameter file. Thus any parameter update is correctly propagated. This fixes a bug where the logfile change was not taken into account under Python.
Make compliant to coding conventions (remove tabs)
Merge branch '1247-add-operators-and-friends-to-GSkymap' into integration
Merge branch '1247-add-operators-and-friends-to-GSkymap' into integration (reverted from commit d809ce80f9e426a6b580362b789c1e15f6b27fff)
Revert max_theta value to original value
Merge branch '1247-add-operators-and-friends-to-GSkymap' into integration
Cross-link Sphinx docs to Doxygen docs
Correct typo
Merge branch 'issue_1068-2' into integration
Put back factor 5 in GModelSpatialRadialGauss::theta_max
Adapt to coding conventions and update Chanhe Log.
Merge branch '1247-add-operators-and-friends-to-GSkymap' into integration

Conflicts:
	ChangeLog
	src/sky/GSkymap.cpp
Add /= and *= operators
Add sqrt friend function
Add missing sqrt friend function
add GCTAExposure and GCTAMeanPsf classes