Universal wheel breaks for Python 3.8.

[jaccarmac]

Because trepan3k tries to use decompyle3 for Pythons 3.7 and 3.8, the universal wheel doesn't work, allowing the debugger to start but with a missing import error message and no elaboration. Manually installing decompyle3 fixes things.

[rocky]

Thanks for the report. I have yanked the universal wheel. Next release I'll make specialized wheels.