Use puppetlabs-postgresql globals for proper versioning
removed deprecated class parameters
Use EXTENSION (new way for spatially-enabled database) for PG>=9.1 & PostGIS>=2.0

 * remove access privileges on postgis_template (not required by default)
 * adapt unit tests
added version_requirement on puppetlabs/postgresql

postgresql::server::postgis was indeed added in version 3.4.0,
thanks to @crawlik and @davidsnyder for pointing out this mistake
Merge pull request #32 from mbornoz/postgis2

Postgis2