Underscore's default ERB-style templates are incompatible with PHP when asp_tags is enabled. As a result, we've settled on an alternative syntax that should be familiar to devs: Mustache-inspired for interpolating and escaping content, and ERB-inspired for execution.
`{{{a}}}` - interpolating
`{{ a }}` - escaping
`<# a #>` - execution
props rmccue. fixes#22344, see #21390.
git-svn-id: http://core.svn.wordpress.org/trunk@22415 1a063a9b-81f0-0310-95a4-ce76da25c4cd