Prelim Work to Migrate from Python 2.7.13 to 3.6.1

[BethanyG]

• [X] Make branch 3.6_rewrite.
• [x] Test to see if current code will run under 3.6 (likely not to) - code did not run, needed changes.
• [x] Test if there are any libraries that are not supported under 3.6.
  • urllib2 was re-configured, needed updated references
  • consider replacing urllib with requests lib instead
  • pattern is not supported for python3, so IngredientAnalyzer.py will need to be re-written with a different lib for the parsetree.
• [x] Begin process of re-writing classes for 3.6, and other upgrades.

[BethanyG]

Closing this issue, as prelim work has more or less been completed. Will create separate issues for adding requests, replacing pattern, etc. etc.