Document new semantics for Closure versions of tags

[hegemonic]

In JSDoc 3.3.0, if you're using the Closure dictionary, and it has higher precedence than the JSDoc dictionary, the behavior of some tags changes:

• The @private tag accepts a type. (In the Closure dictionary, make the 'private' tag more flexible jsdoc#730)
• The @protected tag accepts a type. (For Closure, the 'protected' tag should accept a type jsdoc#731)