Leaflet should be a Peer Dependency

[leesei]

I believe Leaflet should be a Peer Dependency.

[robpvn]

That sounds like a good idea to me!

[robpvn]

OK, so we merged a half-way fix to this by making leaflet a dev dependency, but this might be even better. @w8r, do you have thoughts on this? Want to implement it?

[w8r]

My solution with the plugins I maintain was first to have 2 versions in separate branches, one for 0.7, one for 1.0.x, and publishing to different tags, latest and rc or dev. But then with 1.0 release candidates popping out too often and not being handled correctly by semver, since they are custom suffixes, I grew rather tired and removed leaflet from dependencies and put it into devDependencies. peerDependencies didn't make it any easier, they just throw more warnings with version conflicts (see above about the custom version suffixes). So for the time being for the 1.0 plugins I only have leaflet as a devDependency, until the major version is finally published. That's what I proposed in #116 PR

Thanks for considering my opinion!

[sroucheray]

Leaflet 1.0 is out now !