* Fix getInitialProps in with-apollo example

The code before had two design flaws:

* When we skip WithApollo.getInitialProps we must hoist PageComponent.getInitialProps if it is present.
* We should expose the apolloClient to underlying PageComponent.getInitialProps contexts.

* Add abort check

* Add some comments

* Add client only example page

https://github.com/zeit/next.js/pull/8620#issuecomment-527870886

* Remove connectToDevTools setting in favor default config

https://github.com/apollographql/apollo-client/blob/7eaf4132cd2cd6244260777799406aaa03fcf377/packages/apollo-client/src/ApolloClient.ts#L170-L173

* Remove fetch check

This is done by https://www.npmjs.com/package/isomorphic-unfetch

* Remove apollo-boost

I am removing this package, because we never actually used it.
This is because we use the named export of apollo boost wich resolves to apollo-client.

This way we removed apollo-link-state, apollo-link-error

* Remove redirect code from the client