bug fix

1.there are two or more same branches in ieee118.txt and it can make
mistakes before.
2.the function "LDUDecomposition" in pw_struct.h" contains a big error
before
[1644:AddElement(i, pursuit, ans / d);  =>
AddElement(i, pursuit, (T(0.0) - ans) / d);]
It makes an increase in the number of iterations convergence(I do not
understand why it can be convergence in the case of error)