add .pyc to .gitignore
add user_entropy to new_random_wallet to add protection against a compromised CSPRNG
Get rid of long_to_hex

This is much easier to folow what's going on, and I added a larger
comment to the function to explain it.

This also allows for user_entropy to be a string, which makes much more sense.
update readme to include user_entropy in new_random_wallet
python 3 fix and allow user_entropy to be an int/long as well
Tweaks based on @sbuss thread
- switch to urandom
- use Vitalik's time hack
- hash user_entropy before concatenating (I see no benefit in this)
python 3 fix and change time manipulation to better capture the full #
eliminate pycrypto dependancy
better use of time as entropy source, good catch @sbuss
get rid of unnecessary hashing
add basic unit test
Add mock to requirements
Test that user_entropy actually adds entropy
Document the new parameter
Remove blank line