Enhancement: Transfer_on_hangup has been changed to only be activated by onhook event. The endcall softkey will cancel the transfer and revert to the original caller. (Requested by Antonio)

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@5608 43c1dc8c-776e-4df2-8ef1-6e829299be21