void ToggleBit(unsigned int bit)
The ToggleBit method inverts the bit at the specified bit
position/index of an OEBitVector. Bit position indices are numbered
from zero, and have a maximum of OEBitVector::GetSize()-1. If the
value of 'bit' is greater than or equal to OEBitVector::GetSize(),
the bitmap is resized to bit+1 bits. All of the new bits other than
the one specified in the argument, i.e. the last, are initialized to
zero.