*merge* dev in master

Changes:
  * The logfile is now opened after the file lock has been acquired.
  * The documentation for each plugin is now part of the plugin's module docstring.
  * The documentation is now generated using each plugin's module docstring.
  * **--long-help** command for each plugin that works similar to Linux *man* command.
  * The server and configuration are now included in the **backups**.