Fix usage of sigil constants, use an enum instead
Fix usage of sigil constants, use an enum instead

johnpryan/mustache,xxgreg/mustache,MikeMitterer/mustache,MikeMitterer/dart-mdl-mustache,johnpryan/mustache,xxgreg/mustache,xxgreg/mustache,MikeMitterer/dart-mdl-mustache,MikeMitterer/mustache,johnpryan/mustache,MikeMitterer/dart-mdl-mustache,johnpryan/mustache,MikeMitterer/dart-mdl-mustache,MikeMitterer/mustache,MikeMitterer/dart-mdl-mustache,xxgreg/mustache,MikeMitterer/mustache,MikeMitterer/mustache