scripts: west_commands: verify minimum cmake version

A recent developer experience study has pointed out that it's very
common for people to miss that the minimum cmake version required by
zephyr is higher than that which is commonly packaged by Linux
distributions.

Since this is a serious usability issue, it's worth adding extra
checking from zcmake.py to make sure that west commands which run
cmake always print a sensible error message if the cmake version used
is too old. Make that happen.

Signed-off-by: Marti Bolivar <marti.bolivar@nordicsemi.no>