Vector2.__eq__: Drop the ambiguous & unhelpful definition
Vector2.__eq__: Drop the ambiguous & unhelpful definition

It can easily be misunderstood as “equals if the x and y coordinates are equal”.

Moreover, it's not particularly useful: ppb-vector is meant to be easy to use,
but it is not meant to be a basic course on 2D geometry.

ppb/ppb-vector,ppb/ppb-vector