postgis_extensions_upgrade(). Can't remember which postgis extensions you installed...

postgis_extensions_upgrade().  Can't remember which postgis extensions you installed and are two lazy to figure out and upgrade each with ALTER EXTENSION.
just do

SELECT postgis_extensions_upgrade();

Closes #3896

git-svn-id: http://svn.osgeo.org/postgis/trunk@15970 b70326c6-7e19-0410-871a-916f4a2858ee