Improve code quality using gofmt and go lint

[codenio]

This PR,

• Refactors code using gofmt and go lint to improve code quality.
• Adds scripts to gofmt code and to update required changes
• Adds scripts to go lint and go vet code
• Adds lint stage before build to retain code quality
• Adds Godocs Badge to README.md

preview:
goes from to

[codenio]

@databus23, @mumoshu. Can this be reviewed and merged?

[codenio]

self-reviewed and pushed the changes.

[mumoshu]

@aananthraj Hey! Thanks a lot for your contribution.

This looks great overall!

Only change I'd like to see is to retain the name of DiffManifests so that the method name conforms to the convention of being "verb (+ noun)". I believe Diff was used like a a verb after the *unix diff command.

[codenio]

so that the method name conforms to the convention of being "verb (+ noun)".

I do agree with your point. I had to change it, as it was reported by gofmt or go lint that
package name and func name are same.
Do let me know, if we need to revert back to old form 👍

[mumoshu]

@aananthraj Ah good point. Then just diff.Manifests and diff.Releases without Diff makes sense to me. Would you mind changing code in that way?

It is a breaking change for anyone using helm-diff as a go library. But it isn't an intended use-case at the moment and I'll keep it until I hear from anyone requesting to bring back the go-level API compatibility. That said, please forgive me if I reverted part of this or altered the lint script to ignore errors on the two method names :)

[codenio]

Would you mind changing code in that way?

Sure will make those changes and update here

It is a breaking change for anyone using helm-diff as a go library.

https://godoc.org/github.com/databus23/helm-diff
Godocs says helm-diff is presently not being imported into other golang packages.
So I guess change this will have a very minimalistic impact.

please forgive me if I reverted part of this or altered the lint script to ignore errors on the two method names :)

No issues on this 👍

[codenio]

@mumoshu made those requested changes

[mumoshu]

LGTM. Thanks a lot for your efforts! ☺️

[codenio]

Thanks @mumoshu for the prompt responce and support 👍