add hemdall install

Change-Id: I153cb95fd78eeca382814ddd28b738c65a2bb0bf
diff --git a/_samsung/samsunggalaxys2hercules.markdown b/_samsung/samsunggalaxys2hercules.markdown
index b209b8c..3f56317 100644
--- a/_samsung/samsunggalaxys2hercules.markdown
+++ b/_samsung/samsunggalaxys2hercules.markdown
@@ -22,3 +22,5 @@
 {% include twrpinstall.html %}
 
 {% include odininstall.html %}
+
+{% include heimdallinstall.html %}