Become more independent

i.e. less dependent :r
Anyway, I've removed a dependency we don't use and a dependency that's only a twisted dependency.  I also removed pycrypto, which is only used by db_services and only needed if db_services will be loaded.  The crypt function was easier to fix than I remember.

I left txsockjs in for now as per our discussion last night, and I bumped the version number so that it installs.