Apollo-angular: Support for Angular v5

[CaerusKaru]

Angular will be entering RC for v5.0.0 in roughly a week, so this issue is open to track compatibility issues with the latest version.

One breaking change already shown is the deprecation of OpaqueToken, which is fixed with #316 (potentially).

[kamilkisiela]

First step to support v5 #358

[intellix]

Installing Angular 5 in my project and am blocked by this not being released.
Would be cool if @next/master was published after every commit so we can live on the edge :)

$ npm dist-tag ls apollo-angular
latest: 4.1.4

Another possibility is to add the prepare npm script to allow people to point directly to github branches via support that was added in npm5:

"prepare": "npm run prepublish"

[CaerusKaru]

Compiling errors with AOT, documented here #363