Add checks for multiple yo versions

[SBoudrias]

I've seen this issue a few times. Basically the user have a yo version installed, and their npm now install in a different binary folder. This cause an issue where the user always use the old yo version as their new ones is not found on their path.

I'm unsure how we could detect this, but the issue is clear when you check where npm installs modules against what is returned with which yo (where yo on windows)

Related bug reports on our trackers

• upgrade exsiting yeoman yo#450
• Existing Yeoman generator and npm link yeoman#1618

[johnny-dash]

I actually met the same issues and is there any quick solution for this? Thanks

[eddiemonge]

This is really a problem with npm. I don't see a way to test for this as the user could have it setup like that. This is really more of a npm issue. If we try to be too smart about fixing this, it could have adverse affects.