Remember open view position & size and command line option for selecting counters

[eero-t]

Currently setting gputop-ui up after starting it takes quite a lot of effort, one cannot just start "using" it. Opening the windows, selecting metrics set and correct counters from a metric, in a sensible order etc.

It would help if gputop-ui would remember which views were open and what were their positions and sizes. If gputop-ui cannot open the window in same size anymore, view sizes should be constrained in same scale, so that one can still use the view sizer widget.

Remembering what counters were selected and in which order may not be as useful because they are metrics-set specific and user may want to change that. Saved configuration doesn't transfer as well to another machine with a different GPU model either, because that may have different set of counters.

For counters I propose using command line options, the same ones used by gputop-wrapper command line tool. That way one can have few scripts / desktop icons that open gputop-ui with a counter set that is suitable for what user wants to do (e.g. monitoring GPU stage bottlenecks vs bandwidth usage, as these are in different metrics sets).