The name regexp::properties::RegExpEmpty is not that expressive. Let's
make clear what is going on.

and also make sure that the unique terminating symbol is unique among both
subject and pattern

Some time ago we moved docker image builds into external repository
cd-release (together with packaging). Now that repository is useless
because we built packages here, so let's do the same for docker images.

For local builds it might be good to use rpaths so that the created
executables are linked to the correct libs without modifying
/etc/ld.so.conf for every build-dir.

~/.aqlrc is just another aql script that can be loaded automatically
when the aql shell starts.

You can put standard aql commands inside the file.

It will be in $BUILD_DIR/install