Update PULL_REQUEST_TEMPLATE.md
Update PULL_REQUEST_TEMPLATE.md

I think we should make sure to update the docs whenever we merge a PR.
apollographql/apollo-client,apollostack/apollo-client,calebmer/apollo-client,stevewillard/apollo-client,calebmer/apollo-client,apollostack/apollo-client,apollostack/apollo-client,cesarsolorzano/apollo-client,cesarsolorzano/apollo-client,apollographql/apollo-client,stevewillard/apollo-client,stevewillard/apollo-client,cesarsolorzano/apollo-client,calebmer/apollo-client