* Store subtables in chunks of 100 subtables per blob. Those 100 subtables are stored
  serialized as an array: array($subtableID => subtableBlob). The first 100 subtables are
  stored in "chunk_0", the next 100 subtables are stored in "chunk_1", ...
* Subtable Ids are now consecutive from 1 to X
* We do no longer serialize the whole Row instance when archiving, instead we only
  serialize the Row's array which contains columns, metadata and datatable. This is not
  only more efficient but allows us to refactor the Row instance in the future (although
  we will always have to be BC)
* Faster row implementation: Columns, Metadata and Subtables access is much faster now

refs #5940 moved files into a subfolder framework, added autoloader to remove duplicated code to load autoload.php and to be able to register more autoloaders (eg for test files) on demand. This I got read of many includes that had to be updated all the time and that had to be updated all the time when moving iles

refs #5940 we might stay backwards compatible this way for 2 months. moved some tests from unit to integration and explained when a test is a unit test, an integration test or a system test.

refs #5940 put tests in correct folders, better testsuite names, some tests still fail and I cannot figure out why

Piwik is a free/libre analytics platform. Refs #4455 GNU Package requirement to use free/libre instead of open source