Add option to enter term ID instead of term name in all operations

Issue Summary

There can be duplicate named terms in vocabulary (sometimes by mistake, othertimes by design). Taxonomy Manager needs a way to deal with these situations. Currently, for example if I have 2 terms with same name Foo, and I want 5 other terms to be children of Foo, I can't distinguish between Foo's in move action. So I have to give these Foo's temporary names like Foo 1 and Foo 2, make my vocab manipulations, then switch back to Foo's. I think you agree that this is ugly.