Three window level actions

Added three window level functions to MMAppController. These allow the
window to float on top, stay on bottom or revert back to normal status.

I have also added the commands to the Actions.plist. The commands were
added using the menu.vim file.

runtime/menu.vim

@@ -80,6 +80,9 @@ if has("gui_macvim")
   an <silent> 9998.350 Window.Select\ Previous\ Tab :tabprevious<CR>
   an 9998.360 Window.-SEP2-			    <Nop>
   an <silent> 9998.370 Window.Bring\ All\ To\ Front <Nop>
+  an <silent> 9998.380 Window.Stay\ On\ Bottom <Nop>
+  an <silent> 9998.390 Window.Stay\ On\ Top <Nop>
+  an <silent> 9998.400 Window.Stay\ Level\ Normal <Nop>
 endif
 
 " Help menu
@@ -1255,6 +1258,9 @@ if has("gui_macvim")
   macm Window.Select\ Next\ Tab			key=<D-}>
   macm Window.Select\ Previous\ Tab		key=<D-{>
   macm Window.Bring\ All\ To\ Front		action=arrangeInFront:
+  macm Window.Stay\ On\ Bottom 	action=stayOnBottom:
+  macm Window.Stay\ On\ Top 	action=stayOnTop:
+  macm Window.Stay\ Level\ Normal action=stayLevelNormal:
 
   macm Help.MacVim\ Help			key=<D-?>
   macm Help.MacVim\ Website			action=openWebsite:

src/MacVim/Actions.plist

@@ -72,5 +72,11 @@
 	<string></string>
 	<key>zoomAll:</key>
 	<string></string>
+	<key>stayOnBottom:</key>
+	<string></string>
+	<key>stayOnTop:</key>
+	<string></string>
+	<key>stayLevelNormal:</key>
+	<string></string>
 </dict>
 </plist>

src/MacVim/MMAppController.h

@@ -53,5 +53,8 @@
 - (IBAction)openWebsite:(id)sender;
 - (IBAction)showVimHelp:(id)sender;
 - (IBAction)zoomAll:(id)sender;
+- (IBAction)stayOnBottom:(id)sender;
+- (IBAction)stayOnTop:(id)sender;
+- (IBAction)stayLevelNormal:(id)sender;
 
 @end

src/MacVim/MMAppController.m

@@ -1196,6 +1196,27 @@ fsEventCallback(ConstFSEventStreamRef streamRef,
     [NSApp makeWindowsPerform:@selector(performZoom:) inOrder:YES];
 }
 
+- (IBAction)stayOnBottom:(id)sender
+{
+    ASLogDebug(@"Stay on bottom");
+    NSWindow *keyWindow = [NSApp keyWindow];
+    [keyWindow setLevel:kCGDesktopIconWindowLevel +1];
+}
+
+- (IBAction)stayOnTop:(id)sender
+{
+    ASLogDebug(@"Stay on top");
+    NSWindow *keyWindow = [NSApp keyWindow];
+    [keyWindow setLevel:NSFloatingWindowLevel];
+}
+
+- (IBAction)stayLevelNormal:(id)sender
+{
+    ASLogDebug(@"Stay level normal");
+    NSWindow *keyWindow = [NSApp keyWindow];
+    [keyWindow setLevel:NSNormalWindowLevel];
+}
+
 - (IBAction)coreTextButtonClicked:(id)sender
 {
     ASLogDebug(@"Toggle CoreText renderer");