List all user added state binding ids
l_bind_state_ids(target)vector with state binding ids
either an object of class loon or a vector that specifies the
widget, layer, glyph, navigator or context completely. The widget is
specified by the widget path name (e.g. '.l0.plot'), the remaining
objects by their ids.
Bindings, callbacks, and binding substitutions are described in detail in
loon's documentation webpage, i.e. run l_help("learn_R_bind")
l_bind_state, l_bind_state_get,
l_bind_state_delete, l_bind_state_reorder