Draft: Add logging interface ILogger

Depends on !80 Resolves #35 (closed)

Add ILogger logging interface. Add log utils based on @rparisha2 proposal.

Log levels taken from https://github.com/gabime/spdlog (except "Warn", which has been renamed to "Warning").

The logger implementation only has to implement the Log function.

Please review and discuss.

Cheers, Martin

The program was tested solely for our own use cases, which might differ from yours.

Martin Stump martin.stump@mercedes-benz.com on behalf of Mercedes-Benz Tech Innovation GmbH, Provider Information