Fix osm2pgsql index statement creation

[cklein05]

Fix osm2pgsql index statement creation

Currently, indexes.py creates syntactically wrong CREATE INDEX statements for osm2pgsql indexes (using the --osm2pgsql option). This is because the target field for the index is specified as None (should be 'way'):

CREATE INDEX planet_osm_point_index ON planet_osm_point USING GIST (None);

Additionally, osm2pgsql creates unnamed indexes and so lets the database chooses a meaningful name, which results in <table_name>_way_idx. Since re-indexing won't work with unnamed indexes, indexes.py must use a defined index name. However, I recommend using 'way_idx' as the index name for osm2pgsql indexes (instead of 'index') in order to be in line with osm2pgsql.

CREATE INDEX planet_osm_point_way_idx ON planet_osm_point USING GIST (way);

I've modified indexes.py so that it's emitting CREATE INDEX statements of the second type (named 'way_idx' and using 'way' as the target field). If you actually prefer a different index name, feel free to modify my changes after merging.

Changes proposed in this pull request:

• specify 'way' as the target field for osm2pgsql indexes
• rename osm2pgsql indexes to '<table_name>_way_idx' (as created by osm2pgsql)

Test rendering with links to the example places:

• no impact on rendering