Make self-hosted CLJS compatible

[lilactown]

Things I think would need to happen:

• Convert helix.impl.analyzer to CLJS and make sure it works with self-hosted compiler
• helix.dom
  • remove :clj the reader conditionals; this could increase code size substantially since the CLJS code will include all the macros
• helix.core
  • macros moved into CLJC file; will the tagged literal values work?
• helix.hooks
  • Remove :clj reader conditionals

[rome-user]

Is there a reference for the self-hosted CLJS compiler? I haven't heard of this, but I will be willing to investigate how tagged literals work. Given "self-hosted", I would assume tagged literals use deftype under the hood, but we have to verify this.

[lilactown]

@roman01la created a test bed for self hosted clojurescript that we could use to validate changes https://github.com/roman01la/clojurescript-studio