Close all previous (pre-INS 114) PRs

[lsukova]

I've closed all of the ones that either seemed dead in the water or closable. The rest is up to your discretion @kevinamstutz @dglass19

• Fix "Examples" anchor links.  #85
• Add old questions as table examples #91
• Add variable examples to unix/bash scripts section #100
• Display book version in book #134
• Add Matlab section to the book #144
• Git & R content #147
• Chicago dept of health project #148