Allows keywords when used for relationship types or labels
Merge pull request #524 from systay/label-keywords

Allows keywords when used for relationship types or labels
Revert "Allows keywords when used for relationship types or labels"

This reverts commit ba20369fb33897d878307f07ef226c72578a5a51.
Able to use ephemeral file system in batch inserter as well as specifying
such from a TestGraphDatabase so that batch inserter tests can be
completely in-memory. Many tests uses this feature.