* Add premix persist tool to Makefile to build as separate binary.
* Fix rootBytes.len > 0 assertion defect in HexaryTrie by adding call to com.db.compensateLegacySetup().
* Run hardForkTransition before executing transactions in getBlockWitness.
* Improve logging and add help message.
* Retry requests for block data.
Morden network has not had a working configuration in Nimbus for a few years,
so it's been removed form the main program. Remove it from premix as well.
Signed-off-by: Jamie Lokier <jamie@shareable.org>