Add hotkeys to organize experiments in dashboard

Signed-off-by: jfniedermeyer <justin.niedermeyer@colorado.edu>

RELEASE_NOTES.rst

@@ -38,6 +38,9 @@ Highlights:
    - The "Close all applets" command (shortcut: Ctrl-Alt-W) now ignores docked applets,
      making it a convenient way to clean up after exploratory work without destroying a
      carefully arranged default workspace.
+   - Hotkeys now organize experiment windows in the order they were last interacted with:
+      + CTRL+SHIFT+T tiles experiment windows
+      + CTRL+SHIFT+C cascades experiment windows
 * Persistent datasets are now stored in a LMDB database for improved performance. PYON databases can
   be converted with the script below.
 

artiq/frontend/artiq_dashboard.py

@@ -85,6 +85,18 @@ class MdiArea(QtWidgets.QMdiArea):
         self.pixmap = QtGui.QPixmap(os.path.join(
             artiq_dir, "gui", "logo_ver.svg"))
 
+        self.setActivationOrder(self.ActivationHistoryOrder)
+
+        self.tile = QtWidgets.QShortcut(
+            QtGui.QKeySequence('Ctrl+Shift+T'), self)
+        self.tile.activated.connect(
+            lambda: self.tileSubWindows())
+
+        self.cascade = QtWidgets.QShortcut(
+            QtGui.QKeySequence('Ctrl+Shift+C'), self)
+        self.cascade.activated.connect(
+            lambda: self.cascadeSubWindows())
+
     def paintEvent(self, event):
         QtWidgets.QMdiArea.paintEvent(self, event)
         painter = QtGui.QPainter(self.viewport())

doc/manual/faq.rst

@@ -27,6 +27,16 @@ organize datasets in folders?
 
 Use the dot (".") in dataset names to separate folders. The GUI will automatically create and delete folders in the dataset tree display.
 
+organize experiment windows in the dashboard?
+---------------------------------------------
+
+Experiment windows can be organized by using the following hotkeys:
+
+* CTRL+SHIFT+T to tile experiment windows
+* CTRL+SHIFT+C to cascade experiment windows
+
+The windows will be organized in the order they were last interacted with.
+
 write a generator feeding a kernel feeding an analyze function?
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