MINOR: Docs: Invalid link to WAMP page
Merge pull request #3498 from edlinklater/patch-1

MINOR: Docs: Invalid link to WAMP page
FIX #3458 iframe transport multi file upload FIX #3343, FIX #3148

UploadField now handles multiple file upload through iframe transport
correctly (mainly for IE) as well as upload errors on a per file basis.