yoda: Sanitize option names parsing

Prepare the code for aliases.

Signed-off-by: Pavel Emelyanov <xemul@sacred.ru>
yoda: Option may have long-named aliases

They follow the option name(s) separated with /-s
Like this:

option	foo/f/foo1/foo2

If you don't want a short option, but want aliases then

option	foo//foo1/foo2

Signed-off-by: Pavel Emelyanov <xemul@sacred.ru>
vzctl: Add aliases for velayout option

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