Allow for the absence of an old version

[joshuahhh]

If you're publishing a package for the first time, you won't have a version yet.

[tgvashworth]

Hi @joshuahhh — thanks for suggesting this.

I'm not sure it's the right thing to do in this situation. Is [no-version] a npm-standard placeholder? If not, I'd rather get the right version number. Something like this:

• no version + npm-release patch -> 0.0.1
• no version + npm-release minor -> 0.1.0
• no version + npm-release major -> 1.0.0

The subsequent question is... what happens if you've already published that version? With that in mind, it seems the best thing is to error out.

In that case, the error message could be improved to say:

No version in package.json found.

Please give your package an initial version and `npm publish` it. We suggest `1.0.0`.

What are your thoughts?