preg_replace() /e deprecated

As of PHP 5.5
The preg_replace() /e modifier is now deprecated. Instead, use the
preg_replace_callback() function.
Appending parameters to URI

Parameters where not being attached to the API request preventing from
controlling the request, size, paging, etc.  I needed this
functionality now, though it could probably be better.
Etsy requires HTTPS now

It’s in the docs, needed for all API requests
Typo

Fixing Typo
Building the parameters better

Should actually pass the unit tests
using http_build_query
Querystring Tests

Some tests for appending the URL parameters to the query string
Merge pull request #3 from kylewiedman/master

Compatibility Fixes & adding missing query string parameters