added callstack as a property
added callstack as a property

added callstack as a property so that it can auto complete in Python shell
angr/angr,schieb/angr,angr/angr,angr/angr,tyb0807/angr,schieb/angr,f-prettyland/angr,f-prettyland/angr,iamahuman/angr,iamahuman/angr,schieb/angr,f-prettyland/angr,tyb0807/angr,tyb0807/angr,iamahuman/angr