Fixed some minor issues with the slider tests
Fixed some minor issues with the slider tests

Added messages to tests.
Changed test to check exact value of id instead of existence.
Changed var names to better reflect what they are.

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