Use package.json version field for EARL reports.

[davidlehn]

• This worked with node and karma.
• Is the 'v' prefix important?
• Our versioning setup uses "3.0.2-0" for dev versions, so when creating real reports would want to checkout a released tag like v3.0.x first. (Or fake it by editing package.json)

[gkellogg]

Is the 'v' prefix important?

No, it doesn't matter at all.

Our versioning setup uses "3.0.2-0" for dev versions, so when creating real reports would want to checkout a released tag like v3.0.x first. (Or fake it by editing package.json)

Whatever you would like to see here.