Add a new lightweight package based on handlebars in the README
Add a new lightweight package based on handlebars in the README

Add a new package [just-handlebars-helpers](https://github.com/leapfrogtechnology/just-handlebars-helpers) on the list. 

This is a lightweight package that offers a collection of common handlebars helpers. And it is [fully tested](https://codecov.io/github/leapfrogtechnology/just-handlebars-helpers)
jbboehr/handlebars.js,gautamkrishnar/handlebars.js,mosoft521/handlebars.js,handlebars-lang/handlebars.js,wycats/handlebars.js,wycats/handlebars.js,handlebars-lang/handlebars.js,gautamkrishnar/handlebars.js,jbboehr/handlebars.js,handlebars-lang/handlebars.js,handlebars-lang/handlebars.js,mosoft521/handlebars.js,mosoft521/handlebars.js,mosoft521/handlebars.js,jbboehr/handlebars.js,wycats/handlebars.js,gautamkrishnar/handlebars.js,mosoft521/handlebars.js,wycats/handlebars.js,wycats/handlebars.js,handlebars-lang/handlebars.js