Update MAT documentation after the launch of the pipeline v5

[sloncocs]

Once OONI Pipeline v5 is released, we will need to update the relevant documentation. This includes but is not limited to:

• How to Interpret OONI Data (https://ooni.org/support/interpreting-ooni-data/)
• OONI Explorer User Guide (https://ooni.org/support/ooni-explorer/#measurement-aggregation-toolkit-mat)
• Outreach Kit (https://ooni.org/support/ooni-outreach-kit/)
• FAQ (https://ooni.org/support/faq/)
• Glossary (https://ooni.org/support/glossary/)

More detailed information about the update is hosted here: https://docs.google.com/document/d/1uGSwQQZWX7x8898qDjfoOBymzdIy5viFoofFAyI0B2U/edit?usp=sharing