bug 452716: add about.html to all plug-ins

Signed-off-by: Florian Thienel <florian@thienel.org>
diff --git a/org.eclipse.vex.documentation/build.properties b/org.eclipse.vex.documentation/build.properties
index 150d734..0818a0e 100644
--- a/org.eclipse.vex.documentation/build.properties
+++ b/org.eclipse.vex.documentation/build.properties
@@ -4,5 +4,7 @@
                toctasks.xml,\
                META-INF/,\
                plugin.properties,\
-               help/
-generateSourceBundle=false
\ No newline at end of file
+               help/,\
+               about.html
+generateSourceBundle=false
+src.includes = about.html