DB Scheme changes: alter table placex add column calculated_country_code varchar(2);

DB Scheme changes: alter table placex add column calculated_country_code varchar(2);

function changes:
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Move to ST_PointOnSurface from ST_Centroid in various places to avoid looking up a point outside the polygon
Move to ST_Covers from ST_Contains to include points on admin boundaries
Re-order preference for get_country_code now our data is better. country_osm_grid is now the preffered source.
Fix code to calculate country code in placex_insert, rank_search test was too early
Add extra field to placex 'calculated_country_code' to improve structure of code
Move split_geometery function out of add_location into its own function
Rewrite split_geometery to be more efficient.
Change place_insert to do more updates and less delete/inserts (delete is slow)
Include wikipedia links in details.php ouput
Cleanup no longer used geometry validation (adding overhead)
Include debug statements in function.sql (--DEBUG: ) and add flag to setup.php to turn them on

setup.php:
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add flag --disable-token-precalc to speed up debuging
add flag --index-noanalyse to disable analysising DB at rank 4 and 26 (previously removed, but on my local DB it seems to be required)
add flag --enable-diff-updates (modifier to --create-functions) to turn on the code required for diff updates without having to modify functions.sql
add flag --enable-debug-statements (modifier to --create-functions) to turn on debug warning statements

update.php:
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added flag --no-index to import osmosis changes without indexing them
extend the hack to allow import of JOSM generated osm files

country_grid.sql - reference copy of the sql used to generate the country_osm_grid table, needs cleanup