Revert "Revert "Improves setup manager implementations""

This reverts commit f133ab2550b4e2d6a4232433f92962fb8c875bc1.
Revert "Revert "Improves setup manager implementations""

This reverts commit f133ab2550b4e2d6a4232433f92962fb8c875bc1.
Adds TablesCreateMShop as post-dependency to run these tasks only on existing tables
Fixed overwriting post-dependencies to get the tasks in the correct order again
Merge branch '2014-08-12_setup-test' of https://github.com/nsendetzky/arcavias-core into 2014-08-12_setup-test

Conflicts:
	lib/mwlib/src/MW/Setup/Manager/Multiple.php
Fixes overwriting post-dependencies to get the correct order of the setup tasks
Merge pull request #783 from nsendetzky/2014-08-12_setup-test

Improves setup manager implementations