As seen on Halloweenfest 2015 and my server. Move in any horizontal direction and double-tap crouch to roll. Do it in midair to flip, and hold the second crouch press to continue to flip until you hit the ground. Won't work if you don't have horizontal velocity.
Comes with prefs to disable/enable roll and flip, and make it minigame-only. Note that while in a minigame it grants a brief period of invulnerability sometimes, as the player is in an invisible vehicle while rolling.
note: works on all playertypes, not just the physics jump playertype datablock.
Download:
https://leopard.hosting.pecon.us/dl/hwakn/Player_PhysicsJump.zip