[Feature] Add basically highlight support for {{ anything }}

[zw963]

What I know about Frontend template all use this.

[zw963]

here some example stolen from handlebars-mode.el:

;; Constant regular expressions to identify template elements.
(defconst handlebars-mode-handlebars-token "\\([a-zA-Z_.][a-zA-Z0-9_:=\?!.-]*\s+\\)*[a-zA-Z_.][a-zA-Z0-9_:=\?!.-]*")
(defconst handlebars-mode-section (concat "\\({{[#^/]\s*"
                                   handlebars-mode-handlebars-token
                                   "\s*}}\\)"))

Thanks.

[zw963]

a example:

{{edit-todo class="edit" value=title focus-out="acceptChanges" insert-newline="acceptChanges"}}