* remove License classifier in favor of a SPDX license
expression, #231
* reorganize and cleanup many tests
* add optional group and sep arguments' to .to01(), #230 - as
well as util.ba2hex() and util.ba2base()
* ignore whitespace in util.base2ba() and util.hex2ba()
* check for embedded nul characters when extending (and
initializing) bitarray from string
* improve testing
* add double precision floating point number example
OBS-URL: https://build.opensuse.org/package/show/devel:languages:python/python-bitarray?expand=0&rev=58
