Create an object to extract data from MPC user agents #8

Finished UserAgent implementation w/ validity checks. Implemented call
to generate install from valid user agents. Fixed issue with generating
dummy install content where java and eclipse version arrays would break
causing issues in posted data. Additionally fixed some badly named
variables that no longer made sense. Added MPC user agent heading to
dummy content script to spoof source.

Change-Id: I32877ad6558edfb04c4d3453cf36e4750ad634c8
Signed-off-by: Martin Lowe <martin.lowe@eclipse-foundation.org>