Change notice that postgis_topology_scripts_installed to a debug one

[robe]

Can you please not make this a notice. Every time I look at it I feel like something is wrong because the tone of it makes it sound like my install is corrupt.

SELECT postgis_full_version();
NOTICE:  Function postgis_topology_scripts_installed() not found. Is topology support enabled and topology.sql installed?

I do see it in PostGIS 2.1 too and it's equally annoying, but I'll settle for fixing this in 2.2.

[strk]

r13994, in trunk.