Entity framework tests now being run from Android container

Until now, js tests didn't require authentication. To add authentication, I modified ForcePluginsTest application to run a subclass of SalesforceDroidGapActivity which uses a MockClientManager which returns a RestClient with hard-coded credentials.

JSTestCase was also modified to run all the tests at once and save their result.
Restarting the activity after every test proves to be very unstable. Sooner or later, the whole process would crash. It's not an ideal solution (e.g. timings reported in Eclipse are of off, running a single test in Eclipse will run all of them unless you first modify the getTestNames() method etc), but at least now the all suite of tests goes through.

NB: there are a few tests failures here and there that still need to be looked into.