Fixes several files incorrectly stated a different license from the actual project, as well as the copyright headers included in all files. This change has no effect on the licensing terms, it should clear up a bit of confusion by contributors. Plus the files get a bit smaller, and we have less duplicated information across the entire project.
Overall the project is GPLv2 if not built with Qt, and GPLv3 if it is built with Qt. There are no parts licensed under a different license, all have been adapted from other compatible licenses into GPLv2 or GPLv3.
This header includes all common data between headers used in the plugin. This should improve cross-platform compiling support whenever possible, as all platform-dependent common includes and defines can be done here.
While Gaussian Blur is not a Blur type that really benefits much from linear sampling, it can be used for a slight quality and gpu usage reduction. However for Area and Directional Blur there is a better alternative: Dual Filtering Blur. And as with all other currently implement Linear versions of Blur, only Area and Directional Blur are supported.
This type of Gaussian Blur also has the loading hitch that exists in normal Gaussian Blur.
Related: #45, #6
