Add license property 'include-copyright-binary'.

Add an additional license property: "Must this license be part of a binary distribution?"

To make this clear, rename 'include-copyright' to 'include-copyright-source', so that we
can call the new property 'include-copyright-binary'.

Note that this commit does not yet set this property for the existing licenses-- that requires actually reading them. :-)

Background: In the course of my work it is very useful to know whether the binary form of someone else's product actually must be accompanied by a license, or whether it may be redistributed without.