Additional URL escaping 

I found a related issue with `URI::REGEXP::PATTERN::UNRESERVED`. Whilst this is correct from an RFC point of view, it doesn't satisfy the SmugMug OAuth API. 

This pull request defines a custom regex (based on `URI::REGEXP::PATTERN::UNRESERVED` but ensures apostrophes and parentheses are also encoded). I've commented on this in the code.

As I bonus I've fixed the RSpec deprecations in the tests.