Bitwise operator mutation

The BitwiseOperatorTurtle looks for the following IL OpCodes in your method:

* OpCodes.Or (bitwise OR, |)
* OpCodes.Xor (bitwise XOR, ^)
* OpCodes.And (bitwise AND, &)

It replaces each with each of the others, forming a separate mutant each time. Thus a single XOR operation will generate two mutants. The turtle applies this mutation at the IL level, simply replacing the OpCode for the instruction then re-saving the assembly before running a suitable subset of your tests.