qtmindmap.pro update, it checks qt version >= 4.6

qtmindmap.pro

@@ -1,8 +1,9 @@
-#-------------------------------------------------
+
-#
+#version check qt: some functions introduced in 4.6
-# Project created by QtCreator 2011-05-24T11:24:26
+contains(QT_VERSION, ^4\\.[0-5]\\..*) {
-#
+message("Cannot build Qt Creator with Qt version $${QT_VERSION}.")
-#-------------------------------------------------
+error("Use at least Qt 4.6.")
+}
 
 QT       += core gui svg xml
 
@@ -36,3 +37,5 @@ TRANSLATIONS += lang/qtmindmap_hu.ts \
                 lang/qtmindmap_nb_NO.ts
 
 CODECFORTR    = UTF-8
+
+DESTDIR = .