Multiple panes

[mmalczak]

Add possibility of adding multiple panes

[marmeladapk]

Fresh artiq_dashboard (when ~/.config/artiq/8/artiq_dashboard(...).pyon is deleted) starts without any pane (interesting side effect: experiments then open in new window separate from dashboard)

There are no scroll bars for the workspace when experiment window is placed outside of visible space:
This branch:

upstream:

Naming when closing and opening new panels is weird with (1)

New MDI Area button seems to be on its own panel that can be docked anywhere or even undocked. Instead I would do a + button on the panel next to the tabs (similar to web browsers).

Minimized experiment windows go to the bottom left of the workspace. On upstream, when the window is resized then these minimized windows are moved accordingly to be kept in view. On this branch this happens only in the active workspace, other workspaces are unnafected. Steps: minimizing experiment, switching workspace, resizing dashboard window (making it smaller) then switching back to the original workspace.

enter new name -> enter a new name

Add a hint on hovering over tab "Double click to rename"

[marmeladapk]

Move "+" button to the left of tabs - that way the button and tabs are connected visually.

Resizing dashboard with minimized experiment on another workspace brings the experiment to the correct place if the window is smaller than before but not when it's larger.
Steps: minimizing experiment, switching workspace, resizing dashboard window (making it bigger) then switching back to the original workspace.

[mmalczak]

Probably the behavior of the minimized windows after closing and reopening GUI could be improved.
For now, I leave it as it is, as it's the same as on the main branch.

Above mentioned issues are fixed.