proposal: museum should always check the upload chart version

[scbizu]

Hi, there !

Background

1. Helm only support the valid semver 2 version chart .
2. But chartmuseum allows the non-semantic chart , and the chart cannot be downloaded from remote museum , it will be the museum garbage until we found it and delete it manually .

Proposal

It is better if we can do some semantic version checking when users upload their chat .

Well , as for details , we should add validate code before we PutObject into the backend storage:

	version,err:=cm_repo.ChartVersionFromStorageObject(storage.Object{
		Content: content,
	})

	sem,err:= semver.Parse(version.Metadata.Version)
	if err!=nil {
		// handle error msg
	}

	if !sem.Validate(){
		// return invalid chart version
	}

Leave me the message if you need the PR .

[jdolitsky]

Hello, if you can add this via PR as configurable option that would be great. Maybe --enforce-semver?