We're using hashresh with the has in query string, but was not working properly

[domenicoven]

We're using hashresh with the has in query string, but was not working properly: when used multiple times the hash was queued to the previous one, not updated. Tweaking a little the RegEx it now works properly also with query strings

Changeset:

• added tests for the querystring scenario
• proved it fails when the has is already present in querystring
• made the test pass tweaking the RergEX