Update PSC and code of conduct files

This merge request has a few purposes:

• Update the Project Steering Committee to point to the list of current committee members on our website (rather than having to update it in multiple places)
• Update the Code of Conduct file to point to the version on our website (rather than having it in multiple places)
• Change "community moderators" to "community managers" which is the term our project is currently using
• Update the Code of Conduct response plan to conform with the changes made to the CoC template during the template community review phase
• Add the incident report and remediation report files