Map::Tube::CLI now loads only the officially supported maps (the list in _supported_maps()) instead of every module found under the Map::Tube:: namespace. This fixes spurious "Couldn't require ..." warnings on startup when an unrelated Map::Tube::* module, such as Map::Tube::Server, is installed but one of its dependencies (e.g. Dancer2) is missing.
_supported_maps() is now defined in a BEGIN block, because it is needed at compile time by Module::Pluggable.
--force now loads the requested Map::Tube::<Name> module itself, and reports a clear error if it cannot be loaded.
Added unit tests: xt/version.t and xt/provides.t
Removed unit tests: xt/meta-json.t and xt/meta-yml.t