Renamed a config test case (which had already been modified to use the MConfig facade. Backed-off on the non-publication of MultiPropertiesConfig; will have to refactor a bit. Undid the delayed initialization of MLog. Use of a static initializer is simple, and should be deadlock free if (non-log) clients stick to the MConfig facade.
Refactored MultiPropertiesConfig into an interface (that keeps the name) and a package-visibility-only utility class (ConfigUtils), with a small hole punched in for the log package via MLogConfigSource.