Add special objects handlers to type processor

[MForest7]

Fixed cases when we cannot infer intersection type for string and Object { length: any } etc.

[Lipen]

LGTM

[Lipen]

Regarding the introduced "flipping" of arguments to intersect: we probably want to somehow order the type facts (add val EtsTypeFact.rank: Int) and always check that in intersect(f1, f2), f1.rank <= f2.rank, and recursively call intersect(f2, f1) otherwise. This will guarantee that all cases (intersect overloads) are covered for both cases (f1 & f2 and f2 & f1), and there will be no need to duplicate the code (and somehow ensure that duplicates are actually the same).