About MacVim show "pre-release" when running a pre-release build

This helps the user know whether they are using a relatively untested
build and should consider going back to a main release. We currently
just define "pre-release" build as any release version with a minor
version, e.g. r176.1 is a pre-release, but r176 isn't.

Also, move the order around so we show "MacVim r123 (Vim
9.0.1234)" instead of "Vim 9.0.1234 (MacVim r123)" which is more
consistent with other ways we show version numbers, and this will be
how we show version number when we upgrade to Sparkle 2.4 as well.

Author: ychin

src/MacVim/MMApplication.m

@@ -52,8 +52,12 @@ - (void)orderFrontStandardAboutPanel:(id)sender
             @"CFBundleVersion"];
     NSString *marketingVersion = [[NSBundle mainBundle]
             objectForInfoDictionaryKey:@"CFBundleShortVersionString"];
+
+    BOOL isPrerelease = [version containsSubstring:@"."];
+    NSString *prerelease = isPrerelease ? @"\npre-release" : @"";
+
     NSString *title = [NSString stringWithFormat:
-            @"Vim %@ (MacVim r%@)", marketingVersion, version];
+            @"MacVim r%@ (Vim %@)%@", version, marketingVersion, prerelease];
 
     [self orderFrontStandardAboutPanelWithOptions:
             [NSDictionary dictionaryWithObjectsAndKeys: