Added brief descriptions to documentation modules.
Added brief descriptions to documentation modules.

mittinatten/freesasa,JoaoRodrigues/freesasa,JoaoRodrigues/freesasa,JoaoRodrigues/freesasa,mittinatten/freesasa,mittinatten/freesasa,JoaoRodrigues/freesasa,mittinatten/freesasa