sendMessage via signal plot from file to window,

add severity to messages (black, yellow, red),
add about text,
removed unused texture from resource

QtMeshViewer/Resources/Resources.qrc

@@ -4,7 +4,9 @@
         <file>vshader.glsl</file>
     </qresource>
     <qresource prefix="/images">
-        <file>cube.png</file>
         <file>icon.ico</file>
     </qresource>
+    <qresource prefix="/files">
+        <file>about.txt</file>
+    </qresource>
 </RCC>

QtMeshViewer/Resources/about.txt

@@ -0,0 +1,24 @@
+This is a viewer for .msh files made by Anakin.
+questions, bug reports, requests: http://www.gametoast.com/viewtopic.php?f=29&t=32624
+source code: https://git.rwth-aachen.de/carstenf/OpenGL/tree/master/QtMeshViewer
+
+===============================================================
+Controll:
+left mouse - rotate
+right mouse - move
+scroll - zoom
+space - reset view
+esc - close
+
+tipp: hold the left mouse and do round movement to rotate the object in z-direction
+
+===============================================================
+Known bugs:
+RLE compressed tga files are not supported,
+Most msh files that were not exported through ZETools are not displayed correctly
+
+===============================================================
+Credits:
+ANDEWEGET
+opengl.org
+forum.qt.io