Rewrite web interface

Change-Id: I53db999947a7d0a8da5ef255d9d13a7dbd976ff6
Add task.yaml files

Change-Id: I07af487ab0cfd7528323eaf02b2dc96ddc3c1181
Add pre and post plugins

Change-Id: Ief27a3bf09f3b2b91c8c03b59ebdd7f65077d321
Delete old task files

Change-Id: Ic1f40c9d6a6caf603bfcb02ceb6c825dec670b54
Some minor fixes

Change-Id: I2917c2bce21f50e7b93f08b789fcef51a3b262d0