Revert "fix build with Qt <4.7 (eg. Debian Lucid)"

This reverts commit 841025992ba14667566e59ad804a66a5f8fe78d7.
Revert "creatensis: build installed.db for osgeo4w-setup"

This reverts commit 45f61d07dd40746d9e0dee2a0efaeb0a4b507aac.
Revert "[FEATURE] Add support for gradient fills for polygons"

This reverts commit 5d01f71e2697d4dcdccac2e77d18394fba1e254b.