Alexander Ziegler / ctools

Since the new GApplication logger methods are more compact than the old format the "logTerse()" etc. constructs have been replaced by the new logger methods. At the same time, the chattiness levels have been reviewed with the following behaviour:
- TERSE: only headers
- NORMAL: standard output, only main results or computations
- EXPLICIT: detailed output
- VERBOSE: verbose output, mainly for diagnostics

The new GApplication logger support function take the chattiness level as the first argument.

All global variables have been removed from the example scripts by introducing a main function with the same name as the file that is called from main. Consequently, all variables are local. This is to avoid any problems between global and local scope of variables.

The building of a cuve on the fly raised issue with memory going out of scope. This is fixed by making the CTA event cube a member of ctbin, and having the cube() method returning a reference to that member

# Conflicts:
#	cscripts/csiactcopy.py
#	cscripts/csiactdata.py

This function avoids code duplication in show_pull_histogram.py and show_pull_evolution.py.

All example scripts now use the cscripts.ioutils.get_args_options() function to get arguments and options.

The pyext/ctools/tools.py script is autogenerate with SWIG, hence we cannot anyway control the code quality of this piece of code.

The lsmodel script has been introduced to illustrate GammaLib usage for Fermi/LAT, it does not belong to the ctools.

There was a code duplication in csroot2caldb and csobs2caldb, which is now avoided by exporting the code in the "calutils" module.

The str.format() function does not exist for before Python 2.6, so don't use it!

These functions are not really observation utilities, and they are not really needed either since they encapsulate only a few lines of code.