correct fread, fwrite, fopen return value

[SegFault42]

correction about issue #11.

fread, fopen and fwrite must return 0 or 1 with u32 return value.

if you want to keep u32 return value you hace to cast to (void )1.

[SegFault42]

another commit where i corrected all warning.

-fno-builtin is for this warning : warning: conflicting types for built-in function 'fwrite' [-Wbuiltin-declaration-mismatch]

the best is simply to chose another name for all reserved function name like fwrite ....