REBOL lexer - added detection if code contains REBOL header and so R lexer is not used instead
REBOL lexer - added detection if code contains REBOL header and so R lexer is not used instead

aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments