Bump template cache to c7d7612de6f48463b962d3727d226be3aacd218c

This breaks the build since offline deps aren't updated to match.
Bump versions for Play 2.3.2; offlineTests not working

 Play to 2.3.2
 sbt-remote-control to 1.0-8756df5dedb13e490ab9ce8a11dbb5a0b5c02362
 sbt-echo to 0.1.1.3 (which appears to be newer than 0.1.3 - not sure
   what happened there)
 Added another junit version, plus some explicit plexus and jsch deps.
 Do not understand why any of these were suddenly necessary.

In this commit things are broken; it seems that jsch never gets
downloaded and is not in local-repository after the local-repository-created
task. Then the offlineTests can't find it.
Use 2.11-based sbt for sbt-remote-control and activator-template-cache and ourselves
Akka version 2.3.3 => 2.3.4
Use sbt-rc 7be0ef2928241f9d13137c7cb90f1c30238f1d25

This one uses sbt-echo 0.1.4 which is not broken.
Add two ridiculous hacks for building local repository

 * jsch 0.1.38 for some reason does not download; so just
   download and stuff it in the cache by hand.
 * we get a corrupted ivy.xml for plexus-component-api 1.0-alpha-16
   which doesn't have the right xmlns, so we fix that.

Both hacks have code to self-report when they can be removed.