Rfcat

killing py3 bugs as we find them.
also, since SDCC v3.5.0 is the last version to correctly build RfCat firmware (working on it meeas!), inserted a Makefile catch that will keep you from installing dorked firmware with later versions of SDCC.
moved vstruct inside rflib, so as not to conflict with the real thing when people have Vivisect and/or some other Vstruct using tool installed.

same firmware as 1.9.2, look there for precompiled binaries.

this is a boring release, which is actually pretty awesome.

bugfix: rfcat_bootloader had a python3 bug causing issues with verifying that firmware was correctly pushed
specan: pip install rfcat[specan] installs Pyside2 to make it easier.

anyone with ideas for how to make v2.0.0 `pop`, please drop some issues or hit me with suggestions. :)

the code is relatively stable.
should release v2.0 soon

removed PySide2 from requirements.txt, as it's not available on all platforms RfCat is desired on.
SpecAn now requires `$ pip install PySide2`

bugfix for bug introduced in last checkin. thanks mnhauke !

added "safemode" to allow RfCat startup (with limitations) for borked dongles using firmware compiled with sdcc>3.5.0 (mostly so we can get into bootloader mode without tapping the magic pin headers, but also for troubleshooting)
bugfixes in vstruct and unittests
bugfixes in rfcat_bootloader (py3 works now! although slow verification :( )