Fixing some memory leaks when creating and destroying yajl objects.

* When creating a yajl object using #auto for the command name,
  the auto-generated command name was not being freed.
* When destroying a yajl object, the clientData structure was not
  being freed.
* When destroying a yajl object, the parser was not being freed.
Fixing a call to ckfree that could corrupt memory.

In yajltcl_yajlObjCmd, the call to ckfree to deallocate the automatically
generated object name is being made _before_ the string is returned to Tcl
via a call to Tcl_SetObjResult. This is unsafe and is being corrected.
Merge pull request #7 from dongola7/master

Fix for memory leaks when creating and destroying yajl objects.