Support semantic versioning for packages

[jthomas]

See this ticket for details: https://github.com/maqetta/maqetta/issues/3460

We should allow a user to specify an "X" branch of a package.

[peller]

"1.8.x" or perhaps just "1.8"?

[kitsonk]

Possibly utilise/adapt semver from: https://github.com/isaacs/node-semver

I think if it is done, it should be as compliant with package.json dependencies as possible, because people "just expect" it to work like that.