Improves diagnostic output.

* toString() of Schema Rule Commands return the actual Schema Rule,
  rather than the DynamicRecord that is used to represent it. This
  improves the output of DumpLogicalLog.
* messages.log now always contain the revision (git hash) of the Kernel.
* Exceptions from RecoveringIndexProxy includes information about what
  the index is that is recovering (using the index descriptor).

+ some minor formatting fixes in IdGeneratorImpl.
Don't activate indexes during recovery.

Fix for a failure in recovery of Unique Indexes where recovery would
crash with the message "cannot await recovering index" when recovering a
store where the active log both creates and drops the index in question.

The correctness of this is based on the assumption that there are other
processes (already in place) to make sure that the indexes are activated
post-recovery.
Merge pull request #1413 from thobe/2.0-fix-unique-index-recovery

Don't activate indexes during recovery.

Fixes issue where recovery would crash with "cannot await recovering index".