Feature/class reduction via policy template specialization

[apmccartney]

• fixed osx travis problem
• eliminated Iterator/Vector classes in favor of template specialization OwnershipPolicy tag struct
• added lower and upper limit methods to bivariate probability distribution
• added CompositeInterpolationTableIntegral class mentioned in implementation header was previously missing
• expanded API docs
• InterpolationRegion -> InterpolationTable
• Reduced verbosity of templates depending upon Interpolation schemes
• Updated version number