Added arithmetic.py
Added bug fixes and new functions to openssl.py
Constant-time equality comparison of HMAC strings without dependency
Added fixes for issue #22
replace GPL licence by BSD licence (issue #24)
rewrite test.py with unittest (issue #27)
update CHANGES.txt
merge branch unittest
Merge remote-tracking branch '3/ConstTimeCompare' into 1.5.5
move equals in hash.py and write unittest for it
Merge remote-tracking branch '1/master' into 1.5.5
pep8 on arithmetic.py
Merge remote-tracking branch '1/bitmessage_openssl' into 1.5.5
pep8 on openssl.py and add exception in rand if RAND_bytes failed
update CHANGES.txt and version
fix openssl.RAND_bytes return type
write _equals_bytes for python3