While it used to be required to pass the `--save` flag in order to actually
write the dependency to the project's `package.json` file, this is no longer
the case in recent versions of npm.
* Fix the example for "Using an Existing Schema"
The file caused the following error:
```
const gql = String.raw;
^
SyntaxError: Identifier 'gql' has already been declared
```
* Update migration-two-dot.md
* Update migration-two-dot.md
* remove formatParams
* remove formatParams from documentation
* check for valid query string after persisted query mapping
* fix sentence about different logging and label extensions as experimental
* mark graphql-extensions as more experimental
* change logging to metrics and add section on Engine
* add to the migration guide
* address feedback and add clarity around logFunction
* address feedback for migration guide
This removes an unnecessary instruction to install `apollo-server` when using the middleware option with Apollo Server 2.0.
While this was necessary in earlier versions of the Apollo Server 2.0 alpha and beta releases, it is no longer needed.
* feat: ApolloServer is created and exported by all variants
* docs: add initial docs around exporting ApolloServer
* feat: export gql from integrations
* docs: change apollo-server examples to use express with registerServer
* server: remove registerExpressServer
* core, docs: comment functions, fix api reference, context creation more like middleware args
* docs: fix integrationed typo
