[INTERNAL][FIX] sap.m.CheckBox improved documentation
[INTERNAL][FIX] sap.m.CheckBox improved documentation

Fixes https://github.com/SAP/openui5/issues/1058
-removed unnecessary comments for custom setters

Change-Id: Ic9a872a81ad1caa0aa1a93b03aa4e678d1b1a2ad

SQCLabs/openui5,olirogers/openui5,nzamani/openui5,olirogers/openui5,cschuff/openui5,SQCLabs/openui5,SAP/openui5,olirogers/openui5,nzamani/openui5,SAP/openui5,cschuff/openui5,SAP/openui5,SAP/openui5,nzamani/openui5,SQCLabs/openui5,cschuff/openui5