Windows port

[udif]

Here is a Windows port of the script. The original version had a few issues:

• STL binary files were not opened in raw mode, breaking them due CR/LF issues.
• slicer type checks took into account filename extension (.exe) so I relaxed that.
• I chose a sane location for all the user and global dirs/files on a Windows platform.
• Fixed forward/backward slash directory compatibility by using basename() and catfile().
• Updated README.md with a Windows section, including the specific filenames to be used for the various slicer options.

I was careful, and I hope I didn't break the Linux version, but I haven't ran all checks on the Linux side because I don't have all the slicers installed on my machine.

I also added an --install flag which helps Windows users by not needing to install make just for installation. It should also work on Linux using the existing paths (~/.config and /usr/share).

[ETE-Design]

Looking forward to this merge since I don't have/use Linux :-)

[udif]

@ETE-Design have you tried this branch, is it working for you?

[ETE-Design]

@udif Not yet, still working on an Prototype of an Non-Planar hotend, so hope this will be merged before I'm ready...