Update m2mvector.h
Update m2mvector.h

Fixed m2mvector::erase, should no longer read from unallocated heap memory.
tridonic-com/mbed-client,tridonic-com/mbed-client,tridonic-com/mbed-client,ARMmbed/mbed-client,ARMmbed/mbed-client,ARMmbed/mbed-client