Panels: Updated docs to state that overlay is the default
Panels: Updated docs to state that overlay is the default

hinaloe/jqm-demo-ja,hinaloe/jqm-demo-ja,arschmitz/uglymongrel-jquery-mobile,arschmitz/jquery-mobile,arschmitz/jquery-mobile,arschmitz/uglymongrel-jquery-mobile,arschmitz/uglymongrel-jquery-mobile,startxfr/jquery-mobile,startxfr/jquery-mobile,startxfr/jquery-mobile,hinaloe/jqm-demo-ja,arschmitz/jquery-mobile