fixed #6437
fixed #6437

calendar unit test added.
tests;
+styleClass&inputStyleClass&panelStyle&panelStyleClass
+inpudId&name&placeholder
+showIcon&changeIcon
+inputclicks
+localeChange
+monthClicks
+selectdate
+changeFormat
+min&max date
+disableates
+invalidDays
+timepicker
+multiple selections
+buttonbar
+buttonbar style&styleClass
+month picker
+keyboardEvent
+event emitters

311devs/primeng,WebRota/primeng,primefaces/primeng,sourabh8003/ultimate-primeNg,primefaces/primeng,sourabh8003/ultimate-primeNg,WebRota/primeng,carlosearaujo/primeng,311devs/primeng,aaraggornn/primeng,sourabh8003/ultimate-primeNg,primefaces/primeng,carlosearaujo/primeng,primefaces/primeng,aaraggornn/primeng,WebRota/primeng,aaraggornn/primeng,WebRota/primeng,311devs/primeng,311devs/primeng,sourabh8003/ultimate-primeNg,carlosearaujo/primeng,carlosearaujo/primeng,aaraggornn/primeng