bug in cipt2

[Dr. Paolo Celani]

Hi

In the present implementation CIPT2 does not allow to perform multistate
calculation but only single state, single reference calculations like for example

refstate,1,2
state,1,2

for the second root.
I placed an explicit trap to block multistate calculations in previous versions of the code
but I must have removed it inadvertently as I worked to later versions.
I will make a patch as soon as possible to stop immediately a CIPT2
calculation involving more than 1 reference/state.

Sorry for the inconvenience.

Paolo Celani