Add OPENCV_VERSION_STR to library symbols

src/OpenShotVersion.h.in

@@ -47,6 +47,7 @@
 #cmakedefine AVCODEC_VERSION_STR "@AVCODEC_VERSION_STR@"
 #cmakedefine AVFORMAT_VERSION_STR "@AVFORMAT_VERSION_STR@"
 #cmakedefine AVUTIL_VERSION_STR "@AVUTIL_VERSION_STR@"
+#cmakedefine OPENCV_VERSION_STR "@OPENCV_VERSION_STR@"
 #cmakedefine01 HAVE_IMAGEMAGICK
 #cmakedefine01 HAVE_RESVG
 #cmakedefine01 HAVE_OPENCV