Fix behaviour on decabling a forcefield emitter
Make carbon steel alloying quicker

Taking the same time per alloying cycle as other alloys meant that carbon
steel was being produced painfully slowly, becuase it processes much less
material per cycle than other alloys.  This change halves the cycle time,
which leaves it still processing less material per second than other
alloying processes, but by a less drastic margin.
Redescribe alloying in craft guide

Change "Alloy cooking" to "Alloying", for consistency with the
descriptions of other recipe types.
Update alloying craft guide to match machine

The alloy furnaces have been changed to lay out the input slots
horizontally.  The craft guide should match that, for mnemonic value.
Improve injector interface

Make the injector's mode button lag-resistant.  Display the mode on
the button, as is done with other machines' toggle buttons.  Describe
the modes using the same words that are now used to distinguish the
corresponding pipeworks objects.  Expand name to "self-contained
injector", now that the pipeworks objects are also called "injector".
Show injector item image along with the item name at the head of the form.