Add Cards dropdown to navbar
Add probabilities table to hero component pages
Fix bug in probabilities calculation
Add conditional formatting to probabilities table
Move probabilities table into template tag
Make the probabilities table pretty colours
Centralise definition of probability targets
Make maximum probability target be 6
Use common shade of red
Resolve probability styling to 2dp
Define DIE_SIDES in settings and use it in views
Remove broken bolding of modifiers

@extend rule was broken; could have fixed it but realised that
I don't actually want the bolding, so removed the styles instead