NOOP: Format all layer's SQL code (#917)

I would like to reformat all of our SQL to have a concise coding style.
This makes it far easier to understand the code for a casual contributor,
and lets us spot errors more easily.

Most importantly, it makes it much easier to grep (search) the code because it is more likely to be in the same syntax

Some key changes:
* SQL keywords are always UPPERCASE, e.g. `SELECT WHEN AS END ...`
* types, variables, aliases, and field names (identifiers) are always lower case
* `LANGUAGE 'plpgsql'` is now `LANGUAGE plpgsql` (no quotes)
* a few minor spacing/semicolon cleanups

P.S. Per @TomPohys request, `TABLE` is spelled using upper case despite being a type for consistency with PG Docs. Same for `LANGUAGE SQL` vs `LANGUAGE plpgsql`.

layers/transportation/class.sql

@@ -1,51 +1,58 @@
-CREATE OR REPLACE FUNCTION brunnel(is_bridge BOOL, is_tunnel BOOL, is_ford BOOL) RETURNS TEXT AS $$
-    SELECT CASE
-        WHEN is_bridge THEN 'bridge'
-        WHEN is_tunnel THEN 'tunnel'
-        WHEN is_ford THEN 'ford'
-    END;
+CREATE OR REPLACE FUNCTION brunnel(is_bridge bool, is_tunnel bool, is_ford bool) RETURNS text AS
 $$
-LANGUAGE SQL
-IMMUTABLE STRICT PARALLEL SAFE;
+SELECT CASE
+           WHEN is_bridge THEN 'bridge'
+           WHEN is_tunnel THEN 'tunnel'
+           WHEN is_ford THEN 'ford'
+           END;
+$$ LANGUAGE SQL IMMUTABLE
+                STRICT
+                PARALLEL SAFE;
 
 -- The classes for highways are derived from the classes used in ClearTables
 -- https://github.com/ClearTables/ClearTables/blob/master/transportation.lua
-CREATE OR REPLACE FUNCTION highway_class(highway TEXT, public_transport TEXT, construction TEXT) RETURNS TEXT AS $$
-    SELECT CASE
-        %%FIELD_MAPPING: class %%
-    END;
+CREATE OR REPLACE FUNCTION highway_class(highway text, public_transport text, construction text) RETURNS text AS
 $$
-LANGUAGE SQL
-IMMUTABLE PARALLEL SAFE;
+SELECT CASE
+           %%FIELD_MAPPING: class %%
+           END;
+$$ LANGUAGE SQL IMMUTABLE
+                PARALLEL SAFE;
 
 -- The classes for railways are derived from the classes used in ClearTables
 -- https://github.com/ClearTables/ClearTables/blob/master/transportation.lua
-CREATE OR REPLACE FUNCTION railway_class(railway TEXT) RETURNS TEXT AS $$
-    SELECT CASE
-        WHEN railway IN ('rail', 'narrow_gauge', 'preserved', 'funicular') THEN 'rail'
-        WHEN railway IN ('subway', 'light_rail', 'monorail', 'tram') THEN 'transit'
-    END;
+CREATE OR REPLACE FUNCTION railway_class(railway text) RETURNS text AS
 $$
-LANGUAGE SQL
-IMMUTABLE STRICT PARALLEL SAFE;
+SELECT CASE
+           WHEN railway IN ('rail', 'narrow_gauge', 'preserved', 'funicular') THEN 'rail'
+           WHEN railway IN ('subway', 'light_rail', 'monorail', 'tram') THEN 'transit'
+           END;
+$$ LANGUAGE SQL IMMUTABLE
+                STRICT
+                PARALLEL SAFE;
 
 -- Limit service to only the most important values to ensure
 -- we always know the values of service
-CREATE OR REPLACE FUNCTION service_value(service TEXT) RETURNS TEXT AS $$
-    SELECT CASE
-        WHEN service IN ('spur', 'yard', 'siding', 'crossover', 'driveway', 'alley', 'parking_aisle') THEN service
-    END;
+CREATE OR REPLACE FUNCTION service_value(service text) RETURNS text AS
 $$
-LANGUAGE SQL
-IMMUTABLE STRICT PARALLEL SAFE;
+SELECT CASE
+           WHEN service IN ('spur', 'yard', 'siding', 'crossover', 'driveway', 'alley', 'parking_aisle') THEN service
+           END;
+$$ LANGUAGE SQL IMMUTABLE
+                STRICT
+                PARALLEL SAFE;
 
 -- Limit surface to only the most important values to ensure
 -- we always know the values of surface
-CREATE OR REPLACE FUNCTION surface_value(surface TEXT) RETURNS TEXT AS $$
-    SELECT CASE
-        WHEN surface IN ('paved', 'asphalt', 'cobblestone', 'concrete', 'concrete:lanes', 'concrete:plates', 'metal', 'paving_stones', 'sett', 'unhewn_cobblestone', 'wood') THEN 'paved'
-        WHEN surface IN ('unpaved', 'compacted', 'dirt', 'earth', 'fine_gravel', 'grass', 'grass_paver', 'gravel', 'gravel_turf', 'ground', 'ice', 'mud', 'pebblestone', 'salt', 'sand', 'snow', 'woodchips') THEN 'unpaved'
-    END;
+CREATE OR REPLACE FUNCTION surface_value(surface text) RETURNS text AS
 $$
-LANGUAGE SQL
-IMMUTABLE STRICT PARALLEL SAFE;
+SELECT CASE
+           WHEN surface IN ('paved', 'asphalt', 'cobblestone', 'concrete', 'concrete:lanes', 'concrete:plates', 'metal',
+                            'paving_stones', 'sett', 'unhewn_cobblestone', 'wood') THEN 'paved'
+           WHEN surface IN ('unpaved', 'compacted', 'dirt', 'earth', 'fine_gravel', 'grass', 'grass_paver', 'gravel',
+                            'gravel_turf', 'ground', 'ice', 'mud', 'pebblestone', 'salt', 'sand', 'snow', 'woodchips')
+               THEN 'unpaved'
+           END;
+$$ LANGUAGE SQL IMMUTABLE
+                STRICT
+                PARALLEL SAFE;