[BLOCKER] Deal with "bool", "boolean" and old C standards

we compile Doom using standard C99 (when "true" and "false" weren't reserved words). "boolean" typedef is here:

Lines 80 to 85 in 584155e

    
           typedef enum  
        
           { 
        
               false	= 0, 
        
               true	= 1, 
        
           	undef	= 0xFFFFFFFF 
        
           } boolean;

In the same time ZKLLVM's stdlib uses type "bool"(added in later standards) in ctype.h header.

Need to find a workaround for this problem

still paused - will deal with it when multiple files will be linked

	typedef enum
	{
	false = 0,
	true = 1,
	undef = 0xFFFFFFFF
	} boolean;