1. Fix the problem of compiling NR_RangeToBestCell.c of NR-RRC 15.3.0
2. Fix the problem that default OCTET/BIT STRING value not used in APER
3. Add support of extension group inside CHOICE type used in LTE-RRC 15.3.0
4. Fix the problem that NGAP 15.0.0 ASN.1 can not generate C files