Fix overlap disablement for mysql 8.0 (#55)

mysql 8.0 can only deal with SRID 0, so when the server is
8.0*, this does hacky conversions into temp tables first and
then runs the existing query using those temp tables.

db_store/sql/6_mysql8.up.sql

@@ -0,0 +1,37 @@
+DROP PROCEDURE IF EXISTS fl_nest_filter_overlap;
+CREATE PROCEDURE fl_nest_filter_overlap (IN maximum_overlap double)
+BEGIN
+  DROP TEMPORARY TABLE IF EXISTS overlapNest;
+  IF (SELECT VERSION() LIKE '8.0%') THEN
+    DROP TEMPORARY TABLE IF EXISTS convertedGeosA;
+    DROP TEMPORARY TABLE IF EXISTS convertedGeosB;
+    CREATE TEMPORARY TABLE convertedGeosA AS (
+        SELECT nest_id, m2, ST_GeomFromText(ST_ASTEXT(polygon), 0) as polygon FROM nests WHERE active=1
+    );
+    CREATE TEMPORARY TABLE convertedGeosB AS (
+        SELECT nest_id, m2, ST_GeomFromText(ST_ASTEXT(polygon), 0) as polygon FROM nests WHERE active=1
+    );
+    CREATE TEMPORARY TABLE overlapNest AS (
+      SELECT b.nest_id
+      FROM convertedGeosA a, convertedGeosB b
+      WHERE a.m2 > b.m2 AND
+        ST_Intersects(a.polygon, b.polygon) AND
+        ST_GeometryType(ST_Intersection(a.polygon, b.polygon)) IN ('Polygon', 'MultiPolygon') AND
+        (100 * ST_Area(ST_Intersection(a.polygon,b.polygon)) / ST_Area(b.polygon)) > maximum_overlap
+    );
+  ELSE
+    CREATE TEMPORARY TABLE overlapNest AS (
+      SELECT b.nest_id
+      FROM nests a, nests b
+      WHERE a.active = 1 AND b.active = 1 AND
+        a.m2 > b.m2 AND
+        ST_Intersects(a.polygon, b.polygon) AND
+        ST_GeometryType(ST_Intersection(a.polygon, b.polygon)) IN ('Polygon', 'MultiPolygon') AND
+        (100 * ST_Area(ST_Intersection(a.polygon,b.polygon)) / ST_Area(b.polygon)) > maximum_overlap
+    );
+  END IF;
+  UPDATE nests a, overlapNest b SET a.active=0,a.discarded='overlap',a.pokemon_id=NULL,a.pokemon_form=NULL,a.pokemon_avg=NULL,a.pokemon_count=NULL,a.pokemon_ratio=NULL,a.pokemon_avg=NULL WHERE a.nest_id=b.nest_id;
+  DROP TEMPORARY TABLE overlapNest;
+  DROP TEMPORARY TABLE IF EXISTS convertedGeosA;
+  DROP TEMPORARY TABLE IF EXISTS convertedGeosB;
+END