fixed #11 add missing parameter to expand callback

the function for the dynatree onExpandCallback has two arguments, a
boolean value that indicates if the node shall be expanded or collapsed
and a node. the first parameter was missing in the callback so the node
parameter was used with the wrong type.
Merge branch 'bug/11-active-node-not-updated' into dev
close 10
#10 jslint
Merge branch 'feature/10-configurable-clickFolderMode' into dev