Refs #3378 : initial commit : copy from the 1.0 version
Fixes #3378 : make group creation optional
Fixes #3779: RPM package installation technique version 4.0 uses wrong path for data file (3.0/...)
Merge pull request #155 from jooooooon/bug_3779/rpm_package_installation_technique_version_4_0_uses_wrong_path_for_data_file_3_0_

Fixes #3779: RPM package installation technique version 4.0 uses wrong p...
Merge pull request #139 from ncharles/bug_3378/dev/make_group_creation_optionnal

Fixes #3378 : make group creation optional
Merge branch 'branches/rudder/2.4' into branches/rudder/2.5
Merge branch 'branches/rudder/2.5' into branches/rudder/2.6