iprt/cpp/list.h,iprt/cpp/mtlist.h: Added assertions for index out of range conditions and tried to force those cases to have predictable non-destructive behavior. (Not possible when indexing an empty list, unfortunately.) Fixed RTMemRealloc bugs. Added missing read locking. Also changed the testcase to not wait forever in the multithreaded test2() function.

IPRT: fix assigning of empty lists

Main: add support for Com(Obj)Ptr<IFACE> in our RTC(MT)List classes

com/list: do r71131 right

com/list: implicit RTCString conversion support

com: added Utf8Str specializations of RT*List