[inferrer] Add support for "line" and "circle" PG types

[solnic]

Hanami model expects that line and circle PG types can be automatically inferred, so it would be nice if we could have that supported by PG inferrer.

Here's what Sequel gives us about these types:

# "line"
[:geometric1, {:oid=>600, :db_type=>"point", :default=>nil, :allow_null=>true, :primary_key=>false, :type=>nil, :ruby_default=>nil}]

# circle
[:geometric3, {:oid=>718, :db_type=>"circle", :default=>"'<(15,15),1>'::circle", :allow_null=>true, :primary_key=>false, :type=>nil, :ruby_default=>nil}]

Refs hanami/model#370

[flash-gordon]

It makes sense to add support for the rest of PG geometric datatypes https://www.postgresql.org/docs/9.6/static/datatype-geometric.html

The whole list would be

• point
• line
• circle
• lseg
• box
• path (closed and open)
• polygon

[Morozzzko]

I'll check this out. Probably gonna have something by the end of the week (Feb 04-05)