base64 encoded tokens (with padding) rejected

[troystauffer]

I have tokens that appear to have been generated using base64 encoding instead of base64url encoding (3rd party auth system) and line 8 of verify-stream.js defines the pattern which the token must match. That doesn't currently include '=' padding, which is causing these tokens to be rejected as invalid.

I'm reading through the spec, and while it's pretty clear that token issuers should not include padding, it also appears to recommend that validation should allow for padding.

Thoughts?

[troystauffer]

I created a PR for this: #25