setting log level from custom YAML file will not work for algorithms with no configuration

[c-dilks]

If an algorithm does not read a configuration YAML file, there is no way a user can set its log level from their custom YAML file.

• every algorithm should have a config file that at least sets the default log level
• meson should demand the existence of Config.yaml for each algorithm
• every algorithm's Start() must call ParseYAMLConfig(); perhaps we can think of a better name, e.g. Configure()