sk-api

sk-api is used at run time in 6 crates.

Depender (with downloads and own rev deps)			sk-api version
120	5	sk-core		^2.1.0
120	3	sk-store		^2.1.0
110		sk-driver		^2.1.0
110		sk-tracer		^2.1.0
110		sk-ctrl		^2.1.0
110		skctl		^2.1.0