Search results can become odd without the country search
terms, so make their inclusion a mandatory part of the
setup.
Also adds a new configuration variable to restrict the
languages taken into account by Nominatim.
Utils scripts must be run from the build directory to make sure
we get the right paths. Rename the settings file in source and
replace the original one with an error, so that scripts
fail with an understandable error message when run from the
source directory.
