Update README.md

Add note on fork purpose
Rename wrapExpresssion
Add support for unescaped HTML
- Fix some comment typos
Unit Tests
Update Readme
Update interpolation regex so that it correctly matches multiple {{{..}}} expressions. Use comment-based binding for embedded html instead of a div; because we don't know if the user intends the given html to be inline or block, we can't embed it in an element.