[Rails-devel] Bug fix 3064831: 18EU minors could lay green tiles

[Erik V. <eri...@xs...>]

Fixed a problem where in 18EU minors were allowed to lay green tiles (bug
#3064831, originally reported by John David Galt).
This bug was caused by the LayTile object have a tileColour allowance map
entry {green=0}.
This entry shouldn't have existed, but the zero value wasn't checked for
anywhere either.
Now in two places zero values are checked for.

I think this error has been introduced by a recent change by Stefan on
mapping the layable tile colours.
I haven't tried to pinpoint the origin (which hardly can called a bug), but
only mitigated the consequences by adding checks, which are useful anyway.

Erik.