New Item (Rising Sun) and bug fixes

The next fireblade is the Rising Sun, a katana.  This also takes
mechanics 7,  as I figure it shouldn't be any harder than building the
Firebrand.  The text menus for this one have a sort of "Zen" simplistic
style that I think fits with the usual Far-East tropes with katanas.
The item descriptions for it aren't very good.  I couldn't think of a
good description for a flaming katana, so I just made fun of the idea
instead.  If anyone has any suggestions for something better, I'm all
ears.

I also tweaked the menu text for the Firebrand, and fixed a bug where
you could turn it on even with no fuel.