Revert "Team Board: moving plugins to plugin directory"

This reverts commit 75c78a5cbc66a65cac43afbaef94d07c6e0c45f9.
Revert "Team Board: show associated Artifacts/Discussion"

This reverts commit a3b4928edf08b0b35acf53690108fab9cd79c26f.
Revert "Team Board: add ability to group by"

This reverts commit 4ad492e05938a72f266f93eb3558d594046301f4.