Add UI to show tiles destroyed by Grey widow's sniper rifle

[mischiefmaker]

Given that the pattern isn’t that obvious, and nearly impossible to predict if you’ve never seen that level of the power before, it’d be nice to show an outline of which tiles are affected by the power when choosing a tile to center on.

This might also be useful for X-Force Wolverine’s strike tile power.

[system]

I like this idea. When you select a tile, the other tiles being destroyed can have an X on them. Even though it is easier to tell what’s being destroyed, the hood could you this too.