* Add ATLAS_CHECK_THREAD_SAFETY to G4HitFilter package
   * https://twiki.cern.ch/twiki/bin/viewauth/AtlasComputing/CheckerGccPlugins

Migrate `G4UA::G4HitFilterTool` configuration to use
`simFlags.OptionalUserActionList`. See ATLASSIM-3569.


Former-commit-id: c6e524ba

Former-commit-id: eac7c67d

Former-commit-id: d12c9663

Whitespace, formatting, range-based for loop, removing unused members,
documentation.


Former-commit-id: 46ad08f5

Former-commit-id: 4c238a9b

- Delete all obsolete src/components/*_load.cxx files
- Remove obsolete DECLARE_FACTORY_ENTRIES within
  src/components/*_entries.cxx
- Migrate to DECLARE_COMPONENT macros

The removed macros evaluate to NULL on the Gaudi side and have been
kept only for backwards compatibility.


Former-commit-id: ece8ee48

Former-commit-id: c3487477

Former-commit-id: 00c71b53

The V2 UserAction implementation has been validated for production,
so the obsolete V1 UserAction implementation should now be removed.


Former-commit-id: f39febec

from ChangeLog:

2016-08-10 Andrea Di Simone <andrea.di.simone@cern.ch>
        * removing V1 user action
        * tagging G4HitFilter-00-00-10


Former-commit-id: 9c5d6539

share/G4HitFilter.py: update syntax to work for both V1 and V2 UserActions. ATLASSIM-2226. Tagging G4HitFilter-00-00-09 (G4HitFilter-00-00-09)

	* share/G4HitFilter.py: update syntax to work for both V1 and V2
	UserActions. ATLASSIM-2226
	* tagging G4HitFilter-00-00-09

2016-02-11  John Chapman  <John.Chapman@cern.ch>
	* move headers to src directory.
	* tagging G4HitFilter-00-00-08

2016-01-11 Andrea Di Simone <andrea.di.simone@cern.ch>
	* reduced verbosity
	* tagging G4HitFilter-00-00-07

2016-01-11 Andrea Di Simone <andrea.di.simone@cern.ch>
	* implemented MT action
	* tagging G4HitFilter-00-00-06


Former-commit-id: b9912f64

	* tagging G4HitFilter-00-00-05
	* added missing queryinterface

2015-04-30 Andrea Di Simone <andrea.di.simone@cern.ch>
	* tagging G4HitFilter-00-00-04
	* moving the filter to the new UA infrastructure

2015-01-07  Zach Marshall <ZLMarshall@lbl.gov>
	* Cleaning up requirements file
	* Tagged as G4HitFilter-00-00-03

src/G4HitFilter.cxx - syntax fix for gcc46 compatibility. Also picks up untagged change from W Bell: adding LUCID to the list of hit containers which is checked. Tagged as G4HitFilter-00-00-02 (G4HitFilter-00-00-02)