std-logger

It's used only as a dev dependency in 4 crates.

Number of dependers	std-logger version	Downloads/month
1	0.5.4	850
2	0.4.4	100
1	0.3.6	27

Depender (with downloads and own rev deps)			std-logger version
		a10	dev	^0.5.3
		heph-rt	dev	^0.4.0
	1	heph	dev	^0.4.0
		gaea	dev	^0.3.3