Two new info files: hacking vmintegration

[Gerald Pfeifer]

This weekend 4.1 snapshot installs two new info files, hacking.info and 
vmintegration.info.

I believe these are related to the classpath import last week.  Do we
really want/need these installed as part of a regular GCC install?  If
so, are the names sufficiently conflict-free?  What happens, if someone
installs classpath as well as GCC 4.1?

I've got now preference either way, just wanting to make sure everyone
is aware of and in agreement with this.

Gerald