Loading Magma into the latest Pharo

[Chris Muller]

Some of you may have noticed that Pharo has removed or renamed
"EventSensor" to "InputEventSensor".  This causes a Warning to appear
when installing Magma, that the extension methods applied to
EventSensor will not be loaded.

These methods exist for transparency, so that *if* someone commits an
object that refers to the Sensor global, it will not materialize a new
Sensor instance in other clients, but rather refer directly to the
existing global.

It's the same behavior as when a reference to Smalltalk, Processor,
World, ActiveHand, Transcript or Compiler is committed / materialized.

Sigh.  So, what to do about it?

  a) let it be.  Pharo users, press "Proceed" and be happy.
  b) remove this serialization behavior for Sensor.  Most apps
probably don't try to serialize it anyway..  But if they do...
breakage!
  c) create a new branch of Magma for this and all future Pharo
divergences.  (Someone please volunteer!)

Suggestions?

 - Chris