Fixed a compiler error on Windows
Fixed a compiler error on Windows

The call to sqrt needs to be cast to double to avoid ambiguity.

Change-Id: I017a645ad4357a3a03ee033837da9fad1de10d2c

OpenChemistry/avogadrolibs,ghutchis/avogadrolibs,ghutchis/avogadrolibs,ghutchis/avogadrolibs,cjh1/mongochemweb-avogadrolibs,cjh1/mongochemweb-avogadrolibs,cjh1/mongochemweb-avogadrolibs,ghutchis/avogadrolibs,wadejong/avogadrolibs,wadejong/avogadrolibs,OpenChemistry/avogadrolibs,cjh1/mongochemweb-avogadrolibs,wadejong/avogadrolibs,OpenChemistry/avogadrolibs,OpenChemistry/avogadrolibs,wadejong/avogadrolibs,OpenChemistry/avogadrolibs,ghutchis/avogadrolibs