- Fix: Avoid errors occurring in Chrome now for supportsGoodTextCharPos

- Linting: Avoid Jamilih file in doc linting
- Testing: Add testcafe (ESLint plugin/rules, accessibility test
  (failing), ui test beginnings (passing))
- Docs: Add "Testing" prefix to contributing file
- npm: Bump to 3.0.0-rc.3

grep-jsdoc.js

@@ -50,6 +50,7 @@ console.log(`${output}\nTotal failures found: ${total}.\n`);
 
 function reduceFalseMatches (file, res) {
   switch (file) {
+  case 'editor/external/jamilih/jml-es.js':
   case 'editor/xdomain-svgedit-config-iife.js': // Ignore
     res.line = [];
     break;