[CMake] INSTALL command doesn't behave as documented

[Thomas Arcila]

Hi,

I've just found a bug. Documentation states that RENAME is allowed for  
PROGRAMS
while it's actually refused by CMake.
I've made my way making the renaming before the installation
(using CONFIGURE_FILE(COPYONLY) I don't know if it's the right way)
but I think that's important to be able to install under a different name.

By the way. CMake is a really great tool.
Using it made my life easier: feature detection is great,
cross platform ability is the best I've seen ;)

Thanks,
Thomas