[TAV-432] Fix CSRF bug in interactions.

When replying to an interaction we need to supply the csrf-token in the request
headers so that Rails can satisfy itself that we're not doing something naughty.
If this isn't passed then it silently complains but the authentication system,
such as Devise, might act on it and kill the current user session.
Load pmrpc.js from local assets rather than Taverna Server.

This means we have one less thing to worry about in the proxy section of the
runs controller.
Don't pull in jquery or jquery_ujs automatically.

The including applications should do that and probably are anyway. If we include
them again in Taverna Player we get warnings in the console.
Merge branch 'master' into rh/csrf-passing

* master:
  Don't pull in jquery or jquery_ujs automatically.
  [TAV-433] Fix character encoding bug for large port values.