Add keyboard input RShift, tilde, "no key up" tokens and debug buttons

These are used to add support for vrc debug commands which I personally wanted to add. Because it's a narrow use case the must be enabled manually by adding vrcDebug = true to [utilitiesSettings] in the OpenVRAdvancedSettings.ini file

src/keyboard_input/input_parser.h

@@ -81,12 +81,15 @@ enum class Token
 
     // Misc tokens
     TOKEN_NEW_SEQUENCE,
+    TOKEN_NO_KEYUP_NEXT,
 
     // Modifiers
     MODIFIER_CTRL,
     MODIFIER_ALT,
     MODIFIER_SHIFT,
+    MODIFIER_RSHIFT,
     MODIFIER_SUPER,
+    MODIFIER_TILDE,
 };
 
 std::vector<Token>