add macro ISSUE_1836_replace_overflow_libcom

#define ISSUE_1751_replace_shl_ro               /*FhG: replace shl_ro by overflow-free alternatives*/

#define ISSUE_1770_replace_shr_ro               /* FhG: replace by non-overflow-alternative - BE */

#define ISSUE_1772_replace_shr_o                /* FhG: replace by non-overflow-alternative - BE */

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

#define FIX_1735_W_SHL_SAT_L                    /* FhG: Usage of W_shl_sat_l() */

#define FIX_ISSUE_1792                          /* FhG: fix noise bursts in binaural rendering */