Support unescaped content in handlebar template

[jeanlaurent]

Support for triple mustache does not work. This prevent us from using unescaped content. Content already in html comes escaped without this.

Look for {{{ in handlebar doc for more explanation http://handlebarsjs.com/

[jeanlaurent]

Ok this sort of work.
Only by [[& somecontent ]] which is good.
Still [[[somecontent]]] does not work. But [[{somecontent}]] work, which is kind of super ugly
It also work by registering a specific helper...

[dgageot]

Won't fix. It's hard coded in the Hbs lexer