Package alterator-module-executor: Information

- Fix child's stderr and stdout pipes not closing.

- All backend files are now loaded in the manager, and modules receive a
  pointer to a table with data that contains information about D-Bus objects
  and handlers. One file describes one interface for one module.
- The interaction between the manager and modules has changed: the module now
  returns not xml, but an instance of GDBusInterfaceInfo (it writes a pointer
  to this instance to the table with data received from the manager, a
  pointer to the vtable is also written there).

- Add child process's stdout and stderr through signals.