feat: add an AsLogr function to use flash as a logr.Logger

[clementnuss]

Useful for e.g. Kubernetes controller-runtime, which expects:

a log set of interfaces called logr (https://godoc.org/github.com/go-logr/logr)

This adds 2 imports and probably makes flash a bit "heavier", it's debatable whether this utility function is useful or not :)

[coveralls]

Pull Request Test Coverage Report for Build 1340776183

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.0%) to 99.231%

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Totals
Change from base Build 450325039:	-0.0%
Covered Lines:	129
Relevant Lines:	130

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💛 - Coveralls

[zbindenren]

Useful for e.g. Kubernetes controller-runtime, which expects:

a log set of interfaces called logr (https://godoc.org/github.com/go-logr/logr)

This adds 2 imports and probably makes flash a bit "heavier", it's debatable whether this utility function is useful or not :)

A am not sure if we want to add those dependencies for the k8s use case. It is already possible to use the logger in k8s with one function call:

package main

import (
	"github.com/go-logr/zapr"
	"github.com/postfinance/flash"
)

func main() {
	l := flash.New()

	z := zapr.NewLogger(l.Desugar())

	z.Info("info")
	z.V(0).Info("info")
}

Maybe mention in the Readme how to use the logger for k8s?

@marcsauter What are your thouthts?

[marcsauter]

I agree, mention it in the README should be enough.

[clementnuss]

I have added an example in the README.md

And while I was at it, I also upgrade the module versions :)