Added fixing contacts in skype groups
- If contact is only in one group
- If skype group is empty, kopete will delete it
- grouip ID is number, so it it now interger
- added renaming group
- added deleting group
- every minutes fix skype groups
- support fastest manipulating with skype groups (save skype groups in QMultiHash)
- fixed moving skype contact in kopete between groups (and top level group)

Fixed pinging message in QDBus
Moved hiding skype GUI window from skypedbus to libskype
Change min version of skype protocol from 5 to 6 and max version from 5 to 8