digiline stuff to be more generic, and add various digilines connections
rules to complement mesecons rules.
Mesecons must be present to get the "wallmounted" rules for digilines nodes.
Without mesecons, nodes that want wall rules will get alldir rules instead.
Add mesecons support to table and standing lamps (off -> max -> off).
Add digilines support to all other lights that now support mesecons,
except rope lights, since they're a mesecon conductor.
(will approach that last one later)
Any of these new submods can be run without any other
components that were once part of the big "homedecor"
mod, other than homedecor_common and homedecor_i18n
Reduced dependencies where possible, but each submod still
has its various dependencies more or less the same as before,
i.e. some need basic_materials, others need unifieddyes,
some need building_blocks, and so on.
All of the stuff that used to be under homedecor/handlers
got moved to homedecor_common, as did any models and/or textures
that are used by more than one other homedecor component.
All the miscellaneous items that didn't warrant their own
mod ended up in homedecor_misc, which can also be thought
of as the remains of the original "homedecor" mod, renamed.
