Making sure onSend is called when the upload starts (fix for sequential uploads).
Making sure onSend is called when the upload starts (fix for sequential uploads).

GrizliK1988/PhotoWidget,blueimp/jQuery-File-Upload,Verde1705/verde1705.github.io,blueimp/jQuery-File-Upload,Verde1705/verde1705.github.io,blueimp/jQuery-File-Upload,blueimp/jQuery-File-Upload,blueimp/jQuery-File-Upload,blueimp/jQuery-File-Upload