Ikarus 1.2.2

 - Implement more secure MEM_ReadByte and MEM_WriteByte: Fix crashes and
   make them slightly faster
 - Add missing engine classes for Gothic 1 (see c4bd8b6 for a complete
   list)
 - Add more Hlp_Is_-functions for mobs (see 0112098 for a complete list)
 - Add STR_Lower function (analogous to STR_Upper)
 - Fix hexadecimal conversions: Include upper case characters A to F in
   MEMINT_HexCharToInt and MEMINT_ByteToKeyHex
 - Remove warnings when initializing without camera, info manager or
   spawn manager, e.g. when initializing from Init_Perceptions
 - Fix MEM_GetFuncIDByOffset for functions overwritten with
   MEM_ReplaceFunc, e.g. MEM_ReadInt: Make while-loops more stable
 - Correctly detect end of code stack while tokenizing functions for
   jumps: Avoid infinite loops
 - Improve MEMINT_SwitchG1G2 slightly
 - Prevent possible crash with cached functions in MEM_CallByString