Two small bugs solved: spinbox blocked only if scan starts, and when canceling the roi window gui doesn't crash.

Still the roi app is not properly incorporated. I will try to make everything nice, written as pyqt classes, I think that way this will work.

webcams and webcamROI added. Still this last needs to be integrated to the GUI, but it works on its own.

Small change to make scans works properly. Now they can never escape the scan interval and they dont run if the spinbox value is outisde region of scan. Also, they start and stop softly.

Scans functions corrected, now the time step is 5ms and that way works fine for now. Also dark theme option enabled.

Save as and Open from functions added to the menu. Now you can also choose where to save and load config file. The Save and Load use the default config file in the control_app folder.

some changes, more close to a final solution. I won't use the paramtree for now. Only to create a class which mixes the spinboxes (or checkpoints) with the corresponding D/A outuputs is pending.