typescript-graphql-apollo does not generate watch query operations

**Is your feature request related to a problem? Please describe.**

using typescript-graphql-apollo the generated code creates query and mutation operations, but not apollo's watch query

**Describe the solution you'd like**

have the plugin create a watch method as well (similar to apollo-angular plugin)

**Describe alternatives you've considered**

None, if we want a simple apollo SDK without an added framework