Remove unused images & related files

[emcwhirter-usgs]

There are several images that aren't used on the site any longer from old content or other things, these include:

• src/htdocs/images/staff/Jeff_Fox_sm.jpg
• src/htdocs/images/staff/Gannon_Jennifer.jpg
• src/htdocs/images/staff/Lindsay_Matt_small.jpg
• src/htdocs/images/staff/Murray_Eric_small.jpg
• src/htdocs/images/staff/jack_sm.jpg
• src/htdocs/images/staff/._finn_a.sm.jpg
• src/htdocs/images/partners/._.DS_Store
• src/htdocs/images/lobby_final.png
• src/htdocs/publications/comicbook/._.DS_Store
• src/htdocs/publications/comicbook/images/._.DS_Store
• src/htdocs/publications/comicbook/thumbnails/<everything that begins with a '.'>

[emcwhirter-usgs]

Probably also remove .DS_Store from .gitignore and any other .DS_Store files. I don't think we need to attempt to customize the image directories within github.