Begins to implement GCTAEdispRMF and unit tests (currently unfinished)
Implements first non-zero and last non-zero operators in GVector
Adds random sampling of cdf vectors to GRan - methods sample_cdf for std::vectors and sample_cdf_GVector GVectors
Adds GVector slice method which takes elements between input elements a and b and outputs to a new GVector
Now uses the GRan sample_cdf method to pick random pixel in GModelSpatialDiffuseMap::mc method to reduce code repetition - I just moved the code from here to GRan
Completes my implementation of the GCTAEdispRMF class, and corrects a minor spelling mistake I noticed when reading through GCTAEdispPerfTable
Adds c++ unit tests for the new GCTAEdispRMF class
Adds python unit tests for the new GCTAEdispRMF class
Removes accidentally commited file test/make_solidangle_image.py
Merge remote-tracking branch 'ellisowen/action_1120' into integration

Conflicts:
	inst/cta/Makefile.am
	inst/cta/include/GCTALib.hpp
	inst/cta/pyext/cta.i

Some of the newly introduced methods have been renamed to fit more the GammaLib standards. The GCTAEdispRMF class needs quite some rework, but I merge it in right now to have a working reference of the code. Some initial code modifications have been done, more to come soon.