Support nested indentation rules

[rrudakov]

Hopefully the final piece that concerns semantic indentation.

This change generalize the way we detect indentation for macros and special forms and adds support for nested indentation rules (so, for example, separate function clojure-ts--match-method-body is not needed anymore).

I changed to format of clojure-ts-semantic-indent-rules (hopefully it's OK for the version that has not been yet officially released) from (:block n) to ((:block n)) or optionally ((:block n) (:inner n)), which is more consistent with cljfmt format.
New format allows defining rules like ("letfn" . ((:block 1) (:inner 2 0)))).

clojure-ts--dynamic-indent-for-symbol now converts not only top level rule, but the entire spec.

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[bbatsov]

I changed to format of clojure-ts-semantic-indent-rules (hopefully it's OK for the version that has not been yet officially released) from (:block n) to ((:block n)) or optionally ((:block n) (:inner n)), which is more consistent with cljfmt format.

Yeah, that's fine. Perhaps we can eventually teach CIDER (and maybe clojure-mode as well) to support this format as well, to get closer to the dream of having uniform indentation metadata with cljfmt.

Great change overall!