Update the Python package trove metadata to reflect that the project
is tested to work with the (still in beta) Python3.7 interpreter.
Programming Language :: Python :: 3.4
Programming Language :: Python :: 3.5
Programming Language :: Python :: 3.6
Programming Language :: Python :: 3.4
Programming Language :: Python :: 3.5
Programming Language :: Python :: 3.6
+ Programming Language :: Python :: 3.7
Programming Language :: Python :: 3 :: Only
Topic :: Communications
Topic :: Communications :: BBS
Programming Language :: Python :: 3 :: Only
Topic :: Communications
Topic :: Communications :: BBS