Changes in qgSurf plugin tools

Due to persisting plugin incompatibilities, related to Matplotlib, I've created a new qgSurf version, # 0.3.4. This version is made up by just two tools: "Best fit plane" and "DEM-plane intersection".
The removed 3D surfaces simulation and deformation tools are now available in a pure Python project, "simSurf", developed and tested in Linux Mint and published at: