Revert "typo fix, small code cleanup"

This reverts commit 3a20e0e1d9b258e5f010b6b87329865a6811b5aa.
Revert "create log dir on pre-boot"

This reverts commit ba720a669198239e20f22ca69fdc8bc70dc405e1.
Revert "get rid of rebar"

This reverts commit f1d8f00cc01c3a48af17d225c0ee10c759549e2c.