Python 3 changes

[Beakerboy]

I also turned on github actions. I was going to write some tests myself, but it looks like it's not doing exactly what I was hoping for. A VBA compressed container does not have to start with '\x00Attribut'. For example, the 'dir' stream in the vbaProject.bin is compressed.

I have an independently made version of the decompression algorithm in case you are interested in comparing how I'm handling everything. https://github.com/Beakerboy/vbaProject-Compiler/blob/main/vbaProjectCompiler/decompressor.py