add PROJ.4 version to about dialog

Author: etiennesky

src/app/qgisapp.cpp

@@ -192,6 +192,7 @@
 // GDAL/OGR includes
 //
 #include <ogr_api.h>
+#include <proj_api.h>
 
 //
 // Other includes
@@ -2320,9 +2321,12 @@ void QgisApp::about()
 #endif
     versionString += "</td>";
 
-
     versionString += "<td>" + tr( "QWT Version" ) + "</td><td>" + QWT_VERSION_STR + "</td>";
 
+    versionString += "</tr><tr>";
+
+    versionString += "<td>" + tr( "PROJ.4 Version" ) + "</td><td>" + QString::number( PJ_VERSION ) + "</td>";
+
 #ifdef QGISDEBUG
     versionString += "</tr><tr><td colspan=4>" + tr( "This copy of QGIS writes debugging output." ) + "</td>";
 #endif