Maria Haupt / gammalib

…eval_gradients() methods.

… methods from GTools.

Removed size() method.

Renamed filename() method to url().
Renamed fullname() method to operator().

…parameter in an XML file.

# Conflicts:
#	ChangeLog
#	NEWS
#	README

…for the case that the input map is not normalized (fixes #1584).

…ion::check_value_real() methods.