Begin work on command line version (cljs)
Add externs file, compile prod in advanced mode
Print summary to STDERR instead of STDOUT
Use console.log instead of println
Change escape-chars? to escape-chars, alias escape-chars? to escape-chars
Drop precondition, automatically convert inputs to string
Don't use meta to keep track of terminals and visitors

Using meta is a nice idea but it's slow and will complicate branch
comparision in the future.
Refactor escape
Update tests
Don't use `char?`
Move src/frak/cli.clj -> src/clj/frak/cli.clj
Use the default user ns for `lein repl`
Exit after running -main
Convert pattern to string before printing
Set :init-ns to frak
Rewrite trie construction and rendering, closes #3
Use cljx, change cljsbuild names
Minor test refactoring