setup.py has undeclared dependency on 'bitstring'

The setup.py lacks a mention of the bitstring package:

https://github.com/nsnw/aprspy/blob/c289ecc44cfc0d2475937cfce4a8b8eac10ba680/setup.py#L21

The requirements.txt file lists it correctly:

https://github.com/nsnw/aprspy/blob/c289ecc44cfc0d2475937cfce4a8b8eac10ba680/requirements.txt#L2

This causes failure at import time:

Traceback (most recent call last):
  File "/blah/blah/import-test.py", line 5, in <module>
    import aprspy
  File "/blah/blah/venv/lib/python3.10/site-packages/aprspy/__init__.py", line 11, in <module>
    from .packets.generic import GenericPacket
  File "/blah/blah/venv/lib/python3.10/site-packages/aprspy/packets/generic.py", line 11, in <module>
    from bitstring import Bits
ModuleNotFoundError: No module named 'bitstring'

One can work around it, obviously, but fixing it won't hurt :-)

nsnw / aprspy

setup.py has undeclared dependency on 'bitstring' #13