Extended core library for Clojure/Script that emphasizes:
  * Cross platform API compatibility
  * Flexibility
  * Performance
  * Backwards compatibility

This lib's mostly for my own use and for advanced users that feel
comfortable reading this source. Not providing much beginner-oriented
documentation for this, sorry.

Quick Taoensso naming conventions:
  **foo** - Dynamic var.
  foo!    - Fn with side effects, or that should otherwise be used cautiously.
  foo?    - Truthy val or fn that returns truthy val.
  foo!?   - Fn that has side effects (or requires caution) and that returns
            a truthy val. Note: !?, not ?!.
  foo$    - Fn that's notably expensive to compute (e.g. hits db).
  foo_    - Dereffable val (e.g. atom, volatile, delay, etc.).
  _       - Unnamed val.
  _foo    - Named but unused val.
  ?foo    - Optional val (emphasize that val may be nil).
  foo*    - A variation of `foo` (e.g. `foo*` macro vs `foo` fn).
  -foo    - Public implementation detail or intermediate (e.g. uncoerced) val.
  >foo    - Val "to foo" (e.g. >sender, >host), or fn to put/coerce/transform.
  <foo    - Val "from foo" (e.g. <sender, <host), or fn to take/coerce/transform.
  ->foo   - Fn to put/coerce/transform.