Bug 487189 - Missing legal files in org.eclipse.dltk.sh.doc

Forgot to include about.html in bin.includes.

Change-Id: I9ce414337073f090adee789206415c00653a5a37
Signed-off-by: Alexander Kurtakov <akurtako@redhat.com>
diff --git a/plugins/org.eclipse.dltk.sh.doc/build.properties b/plugins/org.eclipse.dltk.sh.doc/build.properties
index cf70111..d13d95c 100644
--- a/plugins/org.eclipse.dltk.sh.doc/build.properties
+++ b/plugins/org.eclipse.dltk.sh.doc/build.properties
@@ -2,4 +2,5 @@
                META-INF/,\
                userguide/,\
                *.xml,\
-               build.properties
+               build.properties,\
+               about.html