Factor out build_query_string.
Factor out build_query_string.

arlolra/flashproxy,glamrock/flashproxy,arlolra/flashproxy,infinity0/flashproxy,glamrock/flashproxy,glamrock/flashproxy,arlolra/flashproxy,arlolra/flashproxy,arlolra/flashproxy,glamrock/flashproxy,arlolra/flashproxy,glamrock/flashproxy,infinity0/flashproxy,glamrock/flashproxy,infinity0/flashproxy,infinity0/flashproxy,infinity0/flashproxy,infinity0/flashproxy,arlolra/flashproxy