[postgis-devel] {Add,Drop}GeometryColumn wrappers

[strk]

I've made a cleanup of the postgis.sql.in code, removing
the AddGeometryColumn and DropGeometryColumn repetitions.
Now the definitions are unique, while the specific parts
which are different from pgsql version to version are
handled with an small cpp conditional block.

I profited of the cleanup to add a cople of wrappers to both 
functions:

ADDGEOMETRYCOLUMN ( <table>, <column>, <srid>, <type>, <dim> )
DROPGEOMETRYCOLUMN ( <table>, <column> )

Note that I've also added a:

DROPGEOMETRYCOLUMN ( <catalog>, <schema>, <table>, <column> )

All changes are in postgis_new.sql (built from postgis.sql.in)

--strk;