implement sheep shearing

* Added shearing sheeps

* Added empty line

* Changed comment in MobData to say what the middle 1 bit is used for

* Replaced if statements with a switch statement and early returns

* Send mob metadata to players that join

* Fixed mob metadata getting freed when exiting the switch statement

* remove currently unnecessary check

* use bitwise and in place of modulo

* style nitpicks

---------

Co-authored-by: p2r3 <p2r3@p2r3.com>

include/globals.h

@@ -241,7 +241,7 @@ typedef struct {
   uint8_t y;
   short z;
   // Lower 5 bits: health
-  // Middle 1 bit: reserved for future use
+  // Middle 1 bit: sheep sheared, unused for other mobs
   // Upper 2 bits: panic timer
   uint8_t data;
 } MobData;