Minor trailing whitespace cleanup (#596)

Remove extra spaces in a number of files.

layers/boundary/boundary.yaml

@@ -2,8 +2,8 @@ layer:
   id: "boundary"
   description: |
       Contains administrative boundaries as linestrings.
-      Until z5 [Natural Earth data](http://www.naturalearthdata.com/downloads/) is used after which 
-      OSM boundaries ([`boundary=administrative`](http://wiki.openstreetmap.org/wiki/Tag:boundary%3Dadministrative)) 
+      Until z5 [Natural Earth data](http://www.naturalearthdata.com/downloads/) is used after which
+      OSM boundaries ([`boundary=administrative`](http://wiki.openstreetmap.org/wiki/Tag:boundary%3Dadministrative))
       are present from z6 to z14 (also for maritime boundaries with admin_level <= 2 at z4 and z5).
       OSM data contains several [`admin_level`](http://wiki.openstreetmap.org/wiki/Tag:boundary%3Dadministrative#admin_level)
       but for most styles it makes sense to just style `admin_level=2` and `admin_level=4`.

layers/housenumber/housenumber_centroid.sql

@@ -25,7 +25,7 @@ CREATE OR REPLACE FUNCTION housenumber.flag() RETURNS trigger AS $$
 BEGIN
     INSERT INTO housenumber.updates(t) VALUES ('y')  ON CONFLICT(t) DO NOTHING;
     RETURN null;
-END;    
+END;
 $$ language plpgsql;
 
 CREATE OR REPLACE FUNCTION housenumber.refresh() RETURNS trigger AS

layers/housenumber/layer.sql

@@ -1,5 +1,5 @@
 
--- etldoc: layer_housenumber[shape=record fillcolor=lightpink, style="rounded,filled",  
+-- etldoc: layer_housenumber[shape=record fillcolor=lightpink, style="rounded,filled",
 -- etldoc:     label="layer_housenumber | <z14_> z14+" ] ;
 
 CREATE OR REPLACE FUNCTION layer_housenumber(bbox geometry, zoom_level integer)