Update Dolphin version to 4.14.98 for Release Candidate

Using KDE_VERSION_STRING as the Dolphin version was convenient, but it
does not make sense anymore because it is fixed at 4.14.3 now.

REVIEW: 121195

src/main.cpp

@@ -33,7 +33,7 @@ KDE_EXPORT int kdemain(int argc, char **argv)
 {
     KAboutData about("dolphin", 0,
                      ki18nc("@title", "Dolphin"),
-                     KDE_VERSION_STRING,
+                     "4.14.98",
                      ki18nc("@title", "File Manager"),
                      KAboutData::License_GPL,
                      ki18nc("@info:credit", "(C) 2006-2014 Peter Penz, Frank Reininghaus, and Emmanuel Pescosta"));