Improved update performance of transportation_name layer
- Refactored LineString-merging and diff updates in update_transportation_name.sql
- Refactored transportation_route_member_coalesced materialized view to table
- Added analyze statements before update queries during transportation_name.refresh_network and update_osm_route_member
This PR follows #1465 to implement pseudo-route relations for Republic of Ireland road routes as described in the [OSM wiki](https://wiki.openstreetmap.org/wiki/Ireland/Roads). Irish road routes work in the same way as UK road routes in that signage is derived from highway classification on a 1:1 basis. The scheme described in the OSM wiki is confirmed via [overpass query](https://overpass-turbo.eu/s/1por).
This feature follows the implementation currently used for UK road routes, in which a 10m Natural Earth polygon is used to determine which roads are located within Ireland to apply this processing.
This PR implements 3 classes of routes:
* M-roads, which are `highway=motorway` and signed with blue/white lettering.
* N-roads ("national roads"), which are `highway=trunk` or `highway=primary` and are signed with green/yellow lettering.
* R- and L-roads ("regional and local roads"), which are `highway=secondary`, `highway=tertiary` or `highway=unclassified`, and signed with white/black lettering
This PR adds an additional pseudo-network for UK non-primary [routes](https://en.wikipedia.org/wiki/Great_Britain_road_numbering_scheme), which are signed with black on white signage with "A" and "B" prefixes. This scheme is described on the [OSM wiki](https://wiki.openstreetmap.org/wiki/Roads_in_the_United_Kingdom). Adding this third psuedo network is needed for generating shields for UK white/black signage for non-primary routes.
Additionally, this fixes a minor bug under which single-digit refs would have been included. Single-digit refs don't exist in the UK, because the numbering scheme is always prefixed by a letter, e.g. "A4".
I also included documentation updates and fixed the typo where a view was named "bg" instead of "gb".
This PR defines the set of routes in Canada which are equivalent in national importance to the US Interstate Highway System, and are therefore appropriate to render at zoom 4. This creates a sane, connected highway network at this zoom level across the USA and Canada.
This adds two additional network types for Canadian highways, ca-provincial for provincial-level roads, and ca-provincial-arterial for "highest importance" roads that are not part of the Trans-Canada highway but should be regarded as equivalent for low-zoom rendering purposes.
Additionally, this extracts out the country-specific network checks to a separate function in order to define "equivalent top-level networks" by country, providing a place to add additional national definitions as they're added by contributors.
Tomas Pohanka
