[Keyboard] Rebound rev3 (#9101)

* more stoof

* readme update

* reverting keymap

* re-adding userspace

* new userspace needed

* no want 0 under thumb

* gettin fancier with my knob

* macro fix

* had pins for oled ver

* wait, these are the right pins

* reduntant line

* image fix

* get highest layer every day

* whoops

* correct rev name in json

* a few good catches

* what I had planned

keyboards/montsinger/rebound/rebound.h

@@ -22,4 +22,6 @@
     #include "rev1.h"
 #elif defined(KEYBOARD_montsinger_rebound_rev2)
     #include "rev2.h"
+#elif defined(KEYBOARD_montsinger_rebound_rev3)
+    #include "rev3.h"
 #endif