steel-topped cabinets can use either three default steel ingots in a row
immediately above a cabinet, or the thinnest cut of steelblock slab via
Moreblocks' circular saw, above the cabinet.
granite-topped cabinets require the thinnest cut of technic granite slab.
marble-topped cabinects can use either a marble slab from homedecor
modpack's building_blocks mod, or the thinnest cut of technic marble
slab (but not the marble bricks)
since forever.
Also clarify it in the copyright message, spread the license file around
a bit, and remove some useless "last changed" dates since they've been
inaccurate for a long time.
package the two together as a modpack so that regular homedecor users don't
see a functional change, but others can take signs_lib and use it as a
standalone mod.
also get rid of some *~ files
