Ensure consistency of patterns/design in react explorer code, dedupe code where possible

Now that the majority of explorers are migrated to react, let's go back through and make sure we are being consistent across each explorer with regards to patterns and designs. Additionally, let's reduce code duplication where possible. Areas initially thought of as warranty attention include:

• data source implementations (including support for global sort and load all)
• listening for clipboard changings
• customizing columns
• context menu and toolbar config handling
• error handling

Feel free to include/investigate additional areas.

For 1.33, please do independent investigation into coming up with actionable things we can do regarding this topic. After investigationg, discuss together and create engineering issues for 1.34.