Refactorings, changed handling of versioned mode to always check /lastest-URL and read version from version.txt
Added documentation to project
- removed _targetVersion from Application (version changes are now handled by GetdownController)
- _version can now be any string comparable by VersionUtil#compareVersions(String, String)
- removed _targetVersion from Application (version changes are now handled by GetdownController)
- _version can now be any string comparable by VersionUtil#compareVersions(String, String)
- refactored resource so that callers must not know how an instance is build from appdir, appbase and path
- smaller refactoring: extracted Step and UpdateInterface from Application
added tests
added NaturalOrderComparator