Require Qt >=5.14.0 for Qt::{KeepEmptyParts,SkipEmptyParts,endl}

- https://doc.qt.io/qt-5/qt.html#SplitBehaviorFlags-enum
- https://doc.qt.io/qt-5/qt.html#endl

Author: hartwork

src/src.pro

@@ -29,6 +29,12 @@ target.path = $$BINDIR
 DEPENDPATH += .
 QT = core
 
+_MIN_QT_VERSION = 5.14.0
+
+!versionAtLeast(QT_VERSION, $${_MIN_QT_VERSION}) {
+    error("Qt $${QT_VERSION} found but Qt >=$${_MIN_QT_VERSION} required, cannot continue.")
+}
+
 greaterThan(QT_MAJOR_VERSION, 5) {
     QT += core5compat
 }