[CMake] change where package is generated; full name of package with extension

[Tyler Roscoe]

1. I want to change where "make package" deposits the packages it
creates.  Is there a way to do this -- some cpack variable I haven't
found?

2. I want to get a hold of the name (or names) of generated packages. I
know the package will be called myproject.some_extension, but how do I
calculate "some_extension"? Is there some mapping between package type
(TGZ, ZIP, NSIS) and the extension it ends up with (.tar.gz, .zip,
.exe)?

Thanks,
tyler