Merge pull request #545 from kbknapp/v2.7.0

v2.7.0 (2016-06-28)

Documentation

• fix typos (43b3d40b)
• ArgGroup: vastly improves ArgGroup docs by adding better examples (9e5f4f5d, closes #534)

Features

• ArgGroup: one can now specify groups which require AT LEAST one of the args (33689acc, closes #533)

Bug Fixes

• App: using App::print_help now prints the same as would have been printed by --help or the like (e84cc018, closes #536)
• Help:
  • prevents invoking help help and displaying incorrect help message (e3d2893f, closes #538)
  • subcommand help messages requested via help _{now correctly match --help (08ad1cff, closes #539)}

Improvements

• ArgGroup: Add multiple ArgGroups per Arg (902e182f, closes #426)
• Usage Strings: [FLAGS] and [ARGS] are no longer blindly added to usage strings (9b2e45b1, closes #537)
• arg_enum!: allows using meta items like repr(C) with arg_enum!s (edf9b233, closes #543)