Update BUGS

We don't want to send people to the UQM bugzilla with our own issues!
Update ChangeLog

Clarify that this is upstream UQM changes only, link to appropriate online resources for bmod changes
minor cleanup in element.h
Merge branch 'master' of github.com:Roisack/Shiver-Balance-Mod
Merge branch 'master' of github.com:Roisack/Shiver-Balance-Mod into partial_cost