yoda: Fix & vs and in boolean expressions checks

Signed-off-by: Pavel Emelyanov <xemul@sacred.ru>
yoda: Allow for aliases for choices

Each string choice may have aliases separated with /-s

Signed-off-by: Pavel Emelyanov <xemul@sacred.ru>
examples: Add aliases for choices to reflect actual ploop state

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