added first version of new translation tool containing
- method to fetch new translation files from oTrance
- method to fetch files and create a pull request
- helper methods to show available language names/codes
- method to show all translation keys that are used anywhere within the code
- method to list all plugins that contain their own language files
uppdated new language tool to support update for plugin translations file
small fixes
language update  refs #3430
language update DBStats refs #3430
language update ExamplePlugin refs #3430
Refs #4208 refactor all singletons except the hard ones (with custom getInstance()
(some tests failing)
Converged submodules
Refs #4208 refactor some singletons
Updating tests README.md to reflect new Screenshot testing mechanism.
Tweaking tests README.md.
Tweaking tests/README.md again.
Merge pull request #122 from piwik/translationupdates

automatic translation update
submodule update
removed old language update script
Update comment
refactor segment for reusing archives
Converged submodules
trying to use some hooks for visualization, properties are now handled in request/view data objects without any logic, not sure if it works, still an experiment, probably does not work for custom visualization properties
do not allow to overwrite constructor