[BUG] Upgrade Wall Detection Issues

BrokenBot is having issues trying to locate some walls for upgrade, so far the main issue is with level 5 walls.

Forum thread http://forum.brokenbot.org/thread-254.html

[Panderine]

Can confirm this. Walls LVL 5 are detected but when trying to upgrade is says not enough gold is avalaible when there is plenty.

Also an issue with Level 8 walls. May be due to difference of skulls per wall. Please see images in this thread for reference. http://forum.brokenbot.org/thread-825-post-6574.htm