Fixed some layout issues in DataSet
Added clause in measurement, bootstrap and jackknife to skip results that are None
Updated fitting routine in TwoPoint to use standard deviation in correlators.
Added standard deviation of correlator to compute square energy and compute square c
Added ability to pass one numpy array if only one particle and momentum specified
Added docstring comments on change to implementation of error in fitting
Altered checking of standard deviations to ensure at least the required number is passed.
Added constaints as optional arguments to chi squared
Added option in TwoPoint.compute_energy return the square amplitude besides the enrgy
Added some more items to todo list