CLC-3223: Fin Aid messages - supporting 2 aid years in the data stream

https://jira.ets.berkeley.edu/jira/browse/CLC-3223

Get Myfinaid feeds for the current and upcoming year.

MyFinaidProxy
- now requires a term_year parameter in addition to the user_id.
- changed the cache key to include the uid+term_year.
- since there are now multiple vcr recordings, we are now matching the path
  considering the aidYear parameter, which requires telling VCR to ignore
  the :token, :app_id, and :app_key parameters

MyFinaid Model
- The current term year no longer comes from the settings file. It is detected automatically, based on the current month.
- The append! method now requests and processes the current and upcoming term years.
- Adding the human readable term_year (2012-2013) to each finaid entry in the activity for sanity purposes, although this officially belongs to another ticket (CLC-2110)

Settings and tests
- Added a vcr recording for 2014.  Now this recording contains 2 years and will be matched on the path with the aidYear parameter, excluding private parameters
- Added Settings.myfinaid_proxy.test_term_year for faking out the current_term_year in tests and when in fake mode
- Updated the my_fin_aid_spec expectations to anticipate the new number of myfinaid messages retrieved with the current and next term year feeds merged together.

To-do:
- Resolve duplicates: many entries can be considered duplicates between the two terms
- Update dummy json for activities
- Check code thus far with fellow developers, especially the current_term_year method of Myfinaid.rb. This is Ok by Chris as a first implementation