Documenting what each tool accomplishes

[rdmorin]

We don't have a clear way to summarize the inputs/outputs and "purpose" of individual modules. Users currently are expected to just know which modules they need. We should think about, and implement, a system for indicating what each tool does. Perhaps we can start by grouping them and tagging them somehow:

• Variant callers -> CNV callers, SNV callers, SV callers
• Variant integrators -> SNV integrator (SLMS-3), SV integrator (sv_master)

etc