Add inherited members to dict-like classes.

[bdice]

Description

Documents dict-like methods on JSONDict, H5Store, and inherited methods for H5StoreManager.

Motivation and Context

After discussion with @DomFijan, we decided we should document dict-like methods on JSONDict and related classes.

Types of Changes

• Documentation update

Checklist:

• I am familiar with the Contributing Guidelines.
• I agree with the terms of the Contributor Agreement.
• My name is on the list of contributors.
• My code follows the code style guideline of this project.
• The changes introduced by this pull request are covered by existing or newly introduced tests.

If necessary:

• I have updated the API documentation as part of the package doc-strings.
• I have created a separate pull request to update the framework documentation on signac-docs and linked it here.
• I have updated the changelog and added all related issue and pull request numbers for future reference (if applicable). See example below.

[Tobias-Dwyer]

Looks about right.

[codecov]

Codecov Report

Merging #398 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #398   +/-   ##
=======================================
  Coverage   76.40%   76.40%           
=======================================
  Files          45       45           
  Lines        7136     7136           
=======================================
  Hits         5452     5452           
  Misses       1684     1684           

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[bdice]

New feature: all pull requests (including this one) will have ReadTheDocs builds. Click "Show all checks" and look at ReadTheDocs to get a link to this PR's built docs. 😄

[bdice]

@atravitz @DomFijan Feel free to merge this after you review.