WQP Leaflet initial import

Try here: http://jsfiddle.net/mkhines/9RR2v/

A simple Leaflet that accesses the WQP wms proxy service.

Returns contents indicated in the searchParams parameter. Alter this to
change resultset. Displays wqp_sites with differing colors (uses
geoserver sld included) depending on provider field (STORET, NWIS or
STEWARDS). Returns all info in GetFeatureInfo request for up to 50
features at a click. Could customize GetFeatureInfo request results if
propertyName param was included in the proxy service, or use templates
to style the current popup output.