yoda: Classify options for opt vectors switch

We'll be in situations when we'd have to scan for more than one
options array depending on current parse status.

The plan is to switch arrays based on 'req_for'-s and 'for'-s.
This patch generates options groups. Each group matches some
expression (currently -- only a single argument match) and
is about to switch options array.

Signed-off-by: Pavel Emelyanov <xemul@sacred.ru>
yopts: Prepare to handle multiple arg/opt sets

Signed-off-by: Pavel Emelyanov <xemul@sacred.ru>
yoda: Move options set into separate template

We'll have several sets, make it easier to generate them.

Signed-off-by: Pavel Emelyanov <xemul@sacred.ru>
yoda: Move set code generation into a function

Signed-off-by: Pavel Emelyanov <xemul@sacred.ru>
yoda: Prepare for generating numerics for args while assigning one

Signed-off-by: Pavel Emelyanov <xemul@sacred.ru>