custom keybinds multiple keypress fix. [add backslash to Parser] (#513)

* fixed input sending bug not properly releasing keys

* updated to ovr 1.12.5

* added disable oculus api button experimental

* small refactor and fix float and bool bugs

* added nokeyup events to modifier keys when read in, and adjusted  token send to have proper logic

* fixed literal held issue

* added backslash

* fixed sender token parser

* updated version string to dev whoops

* added backslash to documentation for keyboard input

docs/keyboard_input_guide.md

@@ -78,6 +78,7 @@
 | Keypad Minus | `KPMINUS` |
 | Keypad Plus | `KPPLUS` |
 | Enter | `ENTER` |
+| Backslash | `BACKSLASH` |
 
 
 ### Misc symbols

docs/specs/Keyboard_Manager-Parser_Spec.md

@@ -70,6 +70,7 @@ A token is either a modifier symbol, literal symbol, symbol sequence or space ch
 | Keypad Minus | `KPMINUS` |
 | Keypad Plus | `KPPLUS` |
 | Enter | `ENTER` |
+| Backslash | `BACKSLASH` |
 
 
 ### Misc symbols