All of our external dependencies are now provided as Ubuntu packages.
  - the RaXML build uses the Makefile.generic which is the same as what is used by the Debian/Ubuntu packages.
  - fastml is now packaged in PPA for Ubuntu saucy, we'll expand this coverage later.
External source dependencies are removed as they are now all available as .deb packages.
Having removed the source of the external dependencies, we modify the python bindings such that they no longer use them.
Integrated gubbins python bindings tests into the build.