The main slow-down is the overheads of booting up beam with the
'start_clean' boot file (which loads all modules).
Prior to this change, beam is started multiple times in order to
resolve configuration values.
After this change:
* For boot commands such as 'start', 'console' and
'foreground', it starts beam twice:
- 1st is to check platform compatibility
- 2nd is to resolve all configs required for boot in a batch
* For non-boot commands, such as 'ctl' and 'ping', it does not
require to start beam for config resolution at all
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