Add .tar.gz files and THUMB.png files to output created by the pipeline.

[scfleming]

A few more data products that I made for MAST ingestion via scripts, that would be much better if they could be automatically generated by the MTPipeline on output, are:

*-THUMB.png = 200x200 pixel scaled PNG versions of every full-res .png (should be four in total per IPPPSSOOT). The command I used is:
convert -quality 50 -resize 200x200 -colors 255 <file>.png <file>-THUMB.png

Also, I create .tar.gz files that tar all the full-res PNGs and FITS files for a given proposalID_targetDescrip subdirectory. As an example, the file name syntax for subdirectory acs/09059_mp762-pulcova/ is:
hlsp_mt_hst_acs-hrc_all-mp762-pulcova_all_v1-0_bundle.tar.gz