Small patch to fix some things identified this weekend:
- Setting a high controller deadzone can make it impossible to dash
- On Neon metro, if players have different 3D background setting it causes a desync online
- The 2D background doesn't activate for Dash City
- Rare crash seen during an online match ("sync.cpp")
Bonus: added jostling/nudging (players can nudge each other when walking/dashing/shielding/idle)