Rename ViActiveOrganizer to ViActiveOrganization

[marceltaeumel]

In Squeak, there seems to be the practice to call instances of Organizer just anOrganization instead of anOrganizer. For example, there is SystemOrganizer but the global variable SystemOrganization, which is an instances of SystemOrganizer. (Might be just because of the single namespace, though.) For another example, there is ClassDescription >> #organization, which also holds an instance of ClassOrganizer. In the same spirit, our dynamically-scoped variable ViActiveOrganizer should actually be called ViActiveOrganization.

... we might want to rename ViQueryOrganizer to ViOrganizer ... or ViScriptOrganizer? Don't know. Depends on whether it will be organizing Vivide objects in general or just Vivide scripts.