Better think twice before pushing...

In fact, it would be better not to compare the wavelength grid sizes if
most modules change the grid *and* have a new grid of the same size
(that's not the case).

Not all contributions change the wavelengths grid (i.e. igm_attenuation). Optimize this case. It shaves off 1 ms/model.

Remove the possibility to use the same module several times. Simplification of the code ensues. Now sed.info keys are prefixed with the characteristic of the module (stellar, nebular, etc.).

glob is imported in the pcigale/session/configuration.py to allow its use in
the configuration file (with eval).

TODO: write a new configuration pattern to add several files with something
like "files *.fits".

Implement the nebular continuum emission. This has required some refactoring to have some homogeneous naming.

There is maybe a bug triggering the display of the best model figure in
a matplotlib interactive window.

Use a simplified gaussian kernel density estimation for computing the
probability density functions.

Update with Inoue's latest models computed with a BC03 stellar continuum. 124 lines are now included from the FUV to the FIR.

The team will use the projets.lam.fr issue tracker instead.

Modification to savefluxes to have all the contenct of the sed.info
dictionary in the output table. That means that all the SED created with
the modules must have the same sed.info keys.

For a given observation, taking the least chi-square or the least
reduced chi-square is the same thing.