Added features to nock/nock-vcr

Fixes:
https://www.pivotaltracker.com/story/show/45791247
https://www.pivotaltracker.com/story/show/45867055
https://www.pivotaltracker.com/story/show/45867111
https://www.pivotaltracker.com/story/show/45964061
https://www.pivotaltracker.com/story/show/46578325

Added options property bag to record.
Added option to record response bodies to separate files.
Added option to record gunzipped response body
Added option to parse/reformat JSON response bodies to make them more human readable.
Added support for recording non-standard TCP ports (ie. not 80 or 443).
Added generic transform support to nock recording and playback
Added options to specify recorded response body file names