adding the original RNG file from Adrian

Signed-off-by: greenTara <taraathan@gmail.com>
The original RNG did not validate, so I corrected validation problems and then converted to RNC.

Signed-off-by: greenTara <taraathan@gmail.com>
content models modified for Implies and Rules, plus node attributes optionalized
allow for optional key, key ref, xml:base and xml:id attributes (rather than required)
fixed garbling of if, then, else, do patterns, with greater positional independence
through interleave.

Signed-off-by: greenTara <taraathan@gmail.com>
adding temporary examples for Relax NG development

Signed-off-by: greenTara <taraathan@gmail.com>