statspro 6.x-2.0-alpha2

Changes since DRUPAL-6--2-0-ALPHA1:

• task by rsevero: Centralized period name creation in statspro_get_period_info().
• task by rsevero: Implemented drush support for path aggregated reports with configurable periods.
• task by rsevero: Implemented period support in the following drush statspro command options: alert, comments, critical, emergency, error, nodes, path_aggregated, pi, sessions, ualert, ucritical, uemergency, uerror, upi, users, uwarning and warning.
• bug #831328 by bennos: Removed spurious 'dd()' from statspro class method get_stats().
• task #830688 by rsevero: Migrate to Statistics Pro exclusive permissions and using "Statistics Pro" in all permission names.
• task by rsevero: Fixed Coder warnings for statspro.inc.