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

kirbyfan64/pygments-unofficial,kirbyfan64/pygments-unofficial,kirbyfan64/pygments-unofficial,kirbyfan64/pygments-unofficial,kirbyfan64/pygments-unofficial,kirbyfan64/pygments-unofficial,kirbyfan64/pygments-unofficial,kirbyfan64/pygments-unofficial,kirbyfan64/pygments-unofficial,kirbyfan64/pygments-unofficial,kirbyfan64/pygments-unofficial,kirbyfan64/pygments-unofficial,kirbyfan64/pygments-unofficial,kirbyfan64/pygments-unofficial,kirbyfan64/pygments-unofficial,kirbyfan64/pygments-unofficial