make preparing samples.tsv easier

[ctb]

I spent a frustrating time debugging tabs vs spaces vs...

a few thoughts:

• allow yaml input
• allow csv input
• allow excel input (??)
• provide a utility script for checking it

[ctb]

actually, another fun idea -- on reporting, provide an HTML output that links all the samples to their various individual outputs (orig file, trimmed file, fastqc output for either/both, etc.)

[bluegenes]

yes! Been wanting this for a while. Excel should be doable, because pandas, but yaml would be nice. Also utility scripts for checking and/or converting. Need to also think about how to best enable large-scale analyses, e.g. MMETSP, where we have a large number of files that we want to assemble separately, but don't want to provide ~678 diff tsv files