Create CALDB comppliant data structure.
Move IAQ response file in bcf folder.
Add calibration index for COMPTEL response files.
Use GCaldb for response access.

Adapt the code to the usage of GCaldb for response access.
Remove GAMMALIB_CALDB environment variable from code.

The GAMMALIB_CALDB environment variable is specific to GammaLib and does not allow for a transparent usage with ctools. This special things has thus been removed.
Replace GAMMALIB_CALDB by CALDB environment variable.