add stack info member in GError
Submitted by david Han
Now in GError struct ,there no call stack info member, so, we cannot show the stack info in the caller functions. add a stackinfo list member in the GError to recording the callstack info. add a g_error_append_callinfo(...) function to append the callstack info when we after called g_error_new or g_propagate_error and other g_error functions.