make content of {embed} available

[hengeb]

Thank you for this great templating engine, I love it!

It would be great if we could have something like this:

{define myblock, $var}
    some markup
    {$var}
    some more markup
    {block content}default content{/block}
    some other markup
{/define}

{embed myblock, "hello"}
    world
{/embed}

Note: "world" is not wrapped in a {block content} tag.

This should render as:

    some markup
    hello
    some more markup
    world
    some other markup

Here, content is used as a keyword (maybe something like __content is better to avoid conflicts).

With the current version of latte I have to wrap "world" in a block which makes templates harder to read.

Regards,
Henrik