Support for PostGIS

[k0ala]

Many Postgres-based apps use PostGIS, so it would be great to support it from skunk!

[cranst0n]

FWIW, I hacked together some codecs that seem to behave for a few of the PostGIS types in this gist. Maybe of use for a legit PR down the road.

[tpolecat]

Very helpful, thanks!

[cranst0n]

So the codecs in my gist are apparently for the built in postgres geometry types and not PostGIS. So while they may be useful in some capacity, they're not what I originally sold them as. As I get further up to speed on this, I'll hopefully have something applicable to PostGIS to share.

[tpolecat]

The built-in geometry types are useful nonetheless. Thanks!

[kareblak]

The suggested codecs are, as stated, for the postgres geometry types, and should have a place in the skunk core imo.