Allow disabling of html escaping

[lrascao]

This is a rehash of #10, as i'm sure you're aware, bbmustache is being used in relx to template scripts and overlay vars, in this context we don't really need html escaping and it would be useful to disable it completely, this way users wouldn't have to use the {{{ syntax to escape binary values in overlays variables for example.

[soranoba]

I understand these.
However, bbmustache is a mutache library. So, "{{ }}" means html escape.
This can not be changed.

If relx use 1.3.x from 1.0.x, you can be the overwrite in the following way.
But, this method does not mean support forever.

1> bbmustache:render(<<"{{hoge}}">>, #{"hoge" => "<s>hoge</s>"}).         
<<"&lt;s&gt;hoge&lt;/s&gt;">>
2> bbmustache:render(<<"{{={ }=}}{{hoge}}">>, #{"hoge" => "<s>hoge</s>"}).
<<"<s>hoge</s>">>

[soranoba]

NOTE:
Although I am preparing the next release in the branch of the 1.3.x.
Now, this feature is not available on the branch.

[soranoba]

It will add this in v1.5.0, because equivalent function exist in mustache.rb.

{escape_fun, fun((binary()) -> binary())}

I plan to add escape_fun to option.

[lrascao]

👍

[soranoba]

This feature was added in v1.5.0.
Please refer to https://github.com/soranoba/bbmustache/releases/tag/v1.5.0