Modernize LHCbMath

• remove deprecated std::{unary,binary}_function
• remove redundant explicit destructor implementations
• prefer static_assert over BOOST_STATIC_ASSERT
• remove CVS/SVN tags
• add final when possible
• use std::unique_ptr with custom deleter to manage GSL workspace
• prefer compiler generated move constructor
• prefer std::array over C-style arrays
• prefer STL algorithms over raw loops