SecondNature - Advanced Forest Generator

Note: This build will not import the zones from the old plugin, you will have to manually create them again. The old file is not deleted, just ignored by this build. A mostly under the hood update. The regions are now saved to a local database file instead of the custom format I used before. Although this feature does not add much to the plugin as it is, it provides me with the tools necessary to implement very useful features (i.e: forest regions saves) in upcoming updates. The new file is called "second_nature_database.db" and will not import the regions from the previous file. I also improved some smaller aspects of the plugin's command line interface and cleaned up the code significantly.