* optimize util.random_p() by also using bitwise AND in final
step
* fix DeprecationWarning regarding u type code
* add verification tests for internals of util.random_p()
* optimize util.random_p() for n < 100
* add Random Bitarrays documentation
* add statistical tests for random functions
OBS-URL: https://build.opensuse.org/package/show/devel:languages:python/python-bitarray?expand=0&rev=74