Make dashback configurable, fix movement bugs, add double jump forward and back.

src/fighter/state/fall.rs

@@ -2,7 +2,7 @@ use super::{FighterStateContext, FighterStateImpl};
 use crate::fighter::animation::AnimKind;
 use crate::fighter::collision;
 use crate::fighter::state::ground::GroundedStateCommon;
-use crate::fighter::state::land::LandingState;
+use crate::fighter::state::land::{LandingState, LandingType};
 use crate::fighter::state::{FighterState, air, jump};
 
 #[derive(Debug, Clone, Copy, Hash)]
@@ -45,7 +45,7 @@ impl FighterStateImpl for FallState {
             let grounded_common = GroundedStateCommon {
                 current_line_id: res.line_id,
             };
-            Some(FighterState::Land(LandingState { grounded_common }))
+            Some(FighterState::Land(LandingState::create(grounded_common, LandingType::Normal)))
         } else {
             None
         }