lib: internal: cacheimpl: small speed-up: use hashmap for 'canProvide'
lib: internal: nativeresolver: impl: refactoring: new type 'BrokenPair'
lib: internal: nativeresolver: impl: refactoring: new function '__get_next_current_solution'
lib: internal: nativeresolver: impl: __generate_possible_actions: refactoring: also fill action priorities
lib: internal: nativeresolver: impl: refactoring: new method '__fill_and_process_introduced_by'
lib: internal: nativeresolver: impl: resolve: refactoring: got rid of 'checkFailed' variable