Check and abort if more timelevels are requested than time hierarchy supports

[Roland Haas]

In order to provide a more user friendly fix for #626 we want to change Carpet (and PUGH?) such that they check at runtime, when memory is allocated that the number of requested timelevels is less or equal than what the time hierarchy (controlled by the max_timelevels) parameter supports.

This check should be done early and should take the checkpoint tag as well as prolongation operator tags into account.

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