MUC Service Plugin update to 0.2.3

- Bug fix: Unable to join groupchat
Merge pull request #74 from Redor/openfire

MUC Service Plugin update to 0.2.3
User Service Plugin update to 2.0.0

- New restfull API (see readme). The plugin is backward compatible.
- Added new requst to get all or specific users
- The user is now extendible with key / values properties
- Added new requst to get roster entries of a specific users
- Added new requst to get group names of a specific users
- Added new request to add user to a group or remove a user from a group
Merge pull request #75 from Redor/openfire

User Service Plugin update to 2.0.0
User Service plugin update to 2.0.1

- Fixed the problem that authentication type was not saved
Merge pull request #76 from Redor/openfire

User Service plugin update to 2.0.1
User service plugin update to 2.0.2

- Fixed the problem with backward compatibility to user service 1.*
Merge pull request #77 from Redor/openfire

User service plugin update to 2.0.2
Fixed: OF-841 Add a note about UAC to the Installation Guide
Merge pull request #78 from Redor/openfire

Fixed: OF-841 Add a note about UAC to the Installation Guide
OF-754: Lock out user option works incorrectly in some cases
Merge pull request #79 from Redor/openfire

OF-754: Lock out user option works incorrectly in some cases
OF-842: Additional properties in User Properties view
OF-69: Add "Groups user belongs to" column to the User Summary page
Merge pull request #80 from Redor/openfire

OF-842: Additional properties in User Properties view
Merge pull request #81 from Redor/openfire

OF-69: Add "Groups user belongs to" column to the User Summary page