Update package.json version number

[kmturley]

Description

Fixing the jspm install issue:
#857

Code sample

I added the package.json version (which jspm requires for installation)

"version": "2.3.0",

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[kmturley]

I signed it!

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CLAs look good, thanks!

[coveralls]

Coverage remained the same at 93.716% when pulling 2514e36 on kmturley:master into e1dff6f on firebase:master.

[jwngr]

Weird... We actually intentionally set the version number to 0.0.0 and do a string replace on that value when we cut new releases. So I'd prefer not to change it if we can avoid that. Do you know why jspm pulls from the master branch of the GitHub repo instead of from our tagged release commits like Bower?

[kmturley]

Other registries like npm surely use the package.json version aswell? Maybe you can commit the updates?

I believe the default behaviour is that it will look at the master branch. However users can override it by using the semvar versioing format:
https://github.com/jspm/jspm-cli/blob/master/docs/installing-packages.md

jspm install angularfire@^2.3.0

You can also submit an override to the jspm registry repo, which would set the default for every user:
https://github.com/jspm/registry#submitting-a-package-override

[jwngr]

We do commit the updated version number, but only for the commits which we tag as releases (e.g. 8678f72). I think I found a way to make it so that we don't need to use the 0.0.0 placeholder anymore in our release process though. Give me a little bit of time to fix that up and then we can get the version actual numbers back in the package.json.

[kmturley]

Cool, I've not done that with grunt before but it seems npm version is one of the best ways to do it.
https://docs.npmjs.com/cli/version

There is a grunt bump plugin which can do it too