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

.circleci/config.yml

@@ -21,7 +21,7 @@ defaults: &defaults
 
     - run:
         name: Verify screenshots and generate diffs and new screenshots
-        command: node dockers/Screenshotter/screenshotter.js --seleniumIP localhost -b $CIRCLE_JOB --verify --diff --new
+        command: node dockers/Screenshotter/screenshotter.js --selenium-ip localhost -b $CIRCLE_JOB --verify --diff --new
 
     - store_artifacts:
         path: test/screenshotter/new