Changelog:
==========
-* avoid buffer being unnecessarily initialized with 0s in several
functions of the 'bitarray.util' module
-* fix '.count()' type hint in pyi-file
-* improve testing
Signed-off-by: Wang Mingyu <wangmy@fujitsu.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>
