Description

There is very little (none?) documentation on our site with respect to the expected behavior of retryable reads. The only available documentation seems to be embedded in the [retryable reads specification|https://github.com/mongodb/specifications/blob/master/source/retryable-reads/retryable-reads.rst,] which isn't easy to find unless you know what you are looking for and isn't documented in a way that is easily consumable for the average MongoDB User. There should be a documentation page on retryable reads that is analogous to the retryable writes page. 

Scope of changes

Impact to Other Docs

MVP (Work and Date)

Resources (Scope or Design Docs, Invision, etc.)