Occasionally the search results will contain links with arguments such
as 'dq', which was being erroneously used in attempts to extract the 'q'
element from query strings. This enforces that only links with '?q=' or
'&q=' (elements with a standalone 'q' arg) will have the element
extracted.
I also refactored the naming of this element once extracted to be just
'q'. Although this seems counterintuitive, it makes a little more sense
since this element is the one we're extracting. It's a vague url arg
name, but it is what it is.
Bump version to 0.5.2 for hotfix release