HAF script assumes there is a non-empty block_log to be replayed if datadir is specified
Motivation: Installer wants to specify a config.ini file for their hived node, but doesn't want to supply a block_log file. Hived dies because it tries to open and replay the block_log. I tried to get around this by directly using --hived-option instead of --hived-data-dir but got same result. Also tried creating an empty block_log, but the script still inserts a --replay in the call to hived, and this makes hived reject the empty block_log (because I guess when doing a replay it is considered an error if there are no blocks in the block_log).