service: Drop geocode-glib copy

The geocode-glib copy is out-of-date and updating it is not as trivial as
it used to be since geocode-location module is not so independent of the
rest of the code any more. Also geocode-glib doesn't see much changes
these days, especially to the geocode-location module so the effort to
port the code, isn't really worth it.

We already copied over the needed code in a previous commit and now we
ditch our geode-glib internal copy and dependency.

Fixes #88.
3 jobs from drop-gg in 2 minutes and 20 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
passed #73428
ubuntu-16.04

00:01:49

passed #73429
ubuntu-17.10

00:01:55

passed #73430
ubuntu-18.04

00:02:19