Share "auto-detected" UI string and add tool tip

No need to have the same translatable string repeated at all these
places.
Also add tooltip to expand a bit on what "auto-detected" actually means.

Task-number: QTCREATORBUG-25291
Change-Id: I25d43486758ba17256cf7e1ea2eea0ec3d567b62
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@qt.io>
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/plugins/coreplugin/icore.cpp

@@ -490,6 +490,11 @@ QString ICore::crashReportsPath()
         return libexecPath() + "/crashpad_reports/reports";
 }
 
+QString ICore::ideDisplayName()
+{
+    return Constants::IDE_DISPLAY_NAME;
+}
+
 static QString clangIncludePath(const QString &clangVersion)
 {
     return "/lib/clang/" + clangVersion + "/include";