ad 6.x-2.0-beta4

New features:

• feature #173176: support for default notifications with optional per-role granularity
• select ad type with inline AHAH switcher (patch thanks to "neochief")
• feature #416164: optionally display ad channel on admin ads listing page in addition to or instead of ad group
• feature #386796: add ability for modules to modify reports, introduce per-channel reports
• by default, only rebuild cache when cron runs. Set 'ad_cache_file_rebuild_realtime' to TRUE in settings.php $conf array to restore old behavior of rebuilding cache whenever advertisements are changed.
• improve debug output, adding timestamps and memory information
• improve debug output when rebuilding file cache

Bug fixes:

• bug #416110: build proper joins when filtering by channel or premiere status
• bug #404892: only display reports tab and notify tab on advertisement nodes
• Fixed numerous E_ALL notices and warnings.
• only add/update weight probability information when working with ads
• don't rebuild cache multiple times when setting weight probability
• remove unintentional call-time pass-by-references during upgrade