added macro in options.h

#define ISSUE_1796_replace_shl_o                             /* FhG: replace shl_ro by overflow-free alternatives - BE*/

#define ISSUE_1836_replace_overflow_libcom                   /* FhG: replace overflow operators by non-overflow-alternatives - BE */

#define ISSUE_1836_replace_overflow_libcom__remnant          /* FhG: replace remaining overflow operators by non-overflow-alternatives in lib_com - BE */

#define ISSUE_1866_replace_overflow_libdec                   /* FhG: BE - Replace BASOPoverflow operators all over the lib_dec module if Overflow result is not used */

#define FIX_1917_DIRAC_RENDER_PTR_INCR                       /* FhG: fix wrong pointer increment in ivas_dirac_dec_render_sf_fx() for object rendering */