Switch from nomnom to commander (#1496)

* Switch from nomnom to commander

* Fix #1489
* --macro repeatable option replaced with single --macros option with ";"
  separator (until https://github.com/tj/commander.js/issues/674)
* Add missing --max-expand option
* Replace expired --unicode-text-in-math-mode option with --strict
  (https://github.com/Khan/KaTeX/issues/1483#issuecomment-405108291)
* Add instructions for how to run in the opening comments
* Clean up option doc strings

* Implement @ylemkimon's comments

* Fix try/const bug

* Fix use of --selenium-ip

It was a quirk that --seleniumIP worked.  --help lists --selenium-ip.

* Implement comments, restore --macro repeatable argument

* Cleanup

* Restore 0 default for maxExpand

* Fix more comments from @ylemkimon

* npm run dist -> npm run build

In preparation for #1500

* Fix line length error

package.json

@@ -81,7 +81,7 @@
     "dist:zip": "cd dist && tar czf ../katex.tar.gz * && zip -rq ../katex.zip *"
   },
   "dependencies": {
-    "nomnom": "^1.8.1"
+    "commander": "^2.16.0"
   },
   "husky": {
     "hooks": {