Docs (collapsible set): added info about triggering collapse on all items in a set. Fixes #4757
Docs (collapsible set): added info about triggering collapse on all items in a set. Fixes #4757

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