minor documentation changes
Merge pull request #6 from jpf/master

I fixed up the documentation a little bit.
remove node v0.4.x support
replace expresso with mocha
throw if trying to overwrite time in non-test env
Merge pull request #8 from freewil/modernize

Modernize
Pushing version 2.0.2
Merge pull request #9 from freewil/throw-time-overwrite

throw if trying to overwrite time in non-test env
Make verify() follow the specs and return null
Merge pull request #12 from fuzzie360/master

Make verify() follow the specs and actually return null on failure
Replace the equal signs in base32 string
Merge pull request #13 from aw/google-authenticator

Replace the equal signs in base32 string
Fixed issue with hash algorithm using Browserify

Fixes #14.
Merge pull request #15 from martinvl/master

Fixed issue with hash algorithm using Browserify
default opt to {} where appropriate
tests for not passing opt

we just want those to not throw an error,
which is why there's no assertions
Merge pull request #17 from thedufer/master

Make `opt` optional, as the docs describe
Bump release to 2.0.3
add thirty-two to dev-dependencies
Merge pull request #20 from one-time-password/master

add thirty-two to dev-dependencies