Prepare for 2.0.7

git-svn-id: http://svn.osgeo.org/postgis/branches/2.0@12555 b70326c6-7e19-0410-871a-916f4a2858ee
Drop svn checkout step, not needed. Add testing step before upload.

See #2736

git-svn-id: http://svn.osgeo.org/postgis/branches/2.0@12556 b70326c6-7e19-0410-871a-916f4a2858ee
Set last updated version for HOWTO_RELEASE

git-svn-id: http://svn.osgeo.org/postgis/branches/2.0@12561 b70326c6-7e19-0410-871a-916f4a2858ee