Request.from_request factory does not handle multiple GET parameters correctly

When using the Request.from_request factory with a query string, any parameters with the same key in the query string will not be parsed correctly. Only the first value will show up in the Request instance.

This patch adds support for multi valued parameters along with a unit test for using the factory with them.

Please ignore the .gitignore edit. I couldn't figure out how to get the github pull request to skip it.