fixed double-rejecting issue when exception occur in map() or flatMap() and failAloud() is used
* improved ByWidgetGroupOptimizer. Now it recursively scans all widgets directories and groups all widgets' files together (not only files presented in stats)
* introduced app-config bundles loader for DRYness
* improved ByWidgetGroupOptimizer. Now it recursively scans all widgets directories and groups all widgets' files together (not only files presented in stats)
* introduced app-config bundles loader for DRYness