External module function mMcalc - used by 
singleion 
This function is optional and intended to accellerate singleion by vectorizing the temperature and
thus save computation resources when using the option -Tsteps. It has the same parameters as 
mcalc with the following modifications:
- double  T is replaced by Vector & T containing the temperatures for which 
the calculation is to be done. T is replaced by Vector & T containing the temperatures for which 
the calculation is to be done.
- Vector & m  is replaced by Matrix & m which should be filled with column
vectors containing the  magnetic moments  . Each column corresponds to a temperature given as inputVector & T. . Each column corresponds to a temperature given as inputVector & T.