Further trimming and simplifying SUMP device:

- simplified the writing of SUMP commands;
- removed unused configuration options;
- added stubs for advanced (HP165xx-style) triggers.
In progress of adding advanced trigger functionality:

- added lib.tdl as submodule;
- added placeholder pane for configuring the advanced triggers
  in the device configuration dialog;
- added property to determine whether a device supports advanced
  triggers or not.
Started integrating lib.tdl:

- added libraries to run configs (need to determine whether they
  should be embedded);
- added simple editor view to the SUMP config dialog.