Change exp to a peerDependency

[motiz88]

appr's current behaviour is to prefer <app>/node_modules/exp over <app>/node_modules/appr/node_modules/exp - a duplication that exists if the app has a newer or incompatible version of exp as a dependency.

This is useful behaviour - e.g. to synchronise the version of exp between appr and any custom CI scripts used by the app. Moving exp to peerDependencies would simply codify it and make it explicit.

[jevakallio]

Thanks @motiz88. Good shout, let's do this.