WIP Fully qualify enum values

• use https://gitlab.cern.ch/snippets/296 to update all known enum values
• minor drive-by modernizations:
  • prefer std::make_unique
  • prefer minimal scoping of variables
  • replace boost::assign with (implicit) std::initializer_lsit
  • replace BOOST_FOREACH with range-based for loops
  • replace boost::lambda with lambda
  • prefer implicit constructors and destructors
  • add final