add hemdall install

Change-Id: I153cb95fd78eeca382814ddd28b738c65a2bb0bf
diff --git a/_samsung/samsunggalaxya70.markdown b/_samsung/samsunggalaxya70.markdown
index f80ecc8..ddec463 100644
--- a/_samsung/samsunggalaxya70.markdown
+++ b/_samsung/samsunggalaxya70.markdown
@@ -21,3 +21,5 @@
 {% include twrpinstall.html %}
 
 {% include odininstall.html %}
+
+{% include heimdallinstall.html %}