docs: clean up jsdoc comments, namespace organization

[aldeed]

Resolves #4176
Impact: minor
Type: docs

Issue

The generated API documentation, particularly newer GraphQL functions, is not well organized.

Solution

This PR makes changes to the jsdoc comments in many files. Specifically, adding and changing namespace and memberof values.

The generated API doc tree now follows this general pattern:

• Organized at the top level by broad concepts, which loosely map to plugin and collection names, such as "Accounts", "Shop", "Orders", etc.
• Within that, there are /GraphQL, /Methods, and /NoMeteorQueries subnamespaces, and occasionally some variations within those.

Also:

• there is now a Collections namespace with all of the Meteor collections and the Schemas namespace has been cleaned up a bit
• the Components namespace is now for React components only, and helpers have been moved to Components/Helpers namespace

Breaking changes

None

Testing

No code changes to test. Only jsdoc comments were changed.

1. Check out this branch, and meteor npm install followed by npm run docs
2. Go to file:///private/tmp/reaction-docs/index.html in a browser and check out the more organized left-side navigation tree.

[nnnnat]

Looks good! a few conflicts with release-1.12

[aldeed]

@nnnnat I merged in release 1.12 and resolved conflicts