This starts `Pleroma.Web.Endpoint` after all other processes and may
avoid some weird bugs (especially at start/restart).
Also properly ignores starting the gopher's gen_server if disabled.
Related to #85
Everything should now be configured at runtime, with the exception of
the `Pleroma.HTML` scrubbers (the scrubbers used can be
changed at runtime, but their configuration is compile-time) because
it's building a module with a macro.
