Help: Fix configure_file call to use COPYONLY, not COPY_ONLY

The configure_file signature has option 'COPYONLY' (no underscore).
Fix the example in 'cmake-packages.7.rst'.
KWSys: Fix configure_file call to use COPYONLY, not COPY_ONLY
Qt4: Fix configure_file call to use COPYONLY, not COPY_ONLY
Merge branch 'fix-configure_file-COPYONLY' into release