[COOK-2297] more gracefully handle pip packages from VCS and source archives

[Frick]

This small change prevents the (rather specific) use case of specifying a version with a package in version control from causing an error. Currently when a version is specified it will be appended to the resource name, breaking any URLs.

[coderanger]

Doesn't take HTTPS into account.

[Frick]

You're correct, I failed to take that into account. Perhaps a single regex test would be better? I'm not sure of the proper way to update this, though. Update the associated ticket and this pull request or submit a new ticket and pull request?

[coderanger]

Just as a general comment, this makes idempotence much harder to manage.

[Frick]

While I agree that using these types of URLs makes idempotence impossible (since they can point to a specific version or 'latest'), the only other option is to not support them at all. Currently if version is specified with one of these URLs it will throw an error. This patch was just to get around that issue as we use a couple of packages in this manner. And as I stated in the ticket, if you use an :upgrade action with a URL of this type the only way to prevent it from re-installing the package on every chef-client run is by specifying a package_name and version.