Provide AppImages for Linux (amd64) (#29)
+ Add capability to build an AppImage based on the Docker file, which can be download on any Linux distribution with a glibc greater than or equal to CentOS 7.
+ Add a smoke-test script to the Docker image and the AppImage (to ensure everything is okay)
+ Added Python/Pyverilog version checkers
~ Greatly reduced Docker image size by using a multi-layer image
~ Changed CLI slightly so output files have full names and not prefices
- Removed Jinja2 from dependencies
