A future version of CMake may not print the "cmake version" line at the
beginning of the --help-*-list output.  Filter out the line with 'grep'
instead of 'tail' to tolerate output from versions of CMake with and
without the version line.  Match "cmake version", "cpack version", and
"ctest version" in each corresponding completion script.

The orginal patch has been reworked in order to follow
CMake source tree layout habit.
Inspired-By: Igor Murzov <e-mail@date.by>