Site: Switch to SHA512 digest and remove link to Github commit on avatica-go download page
diff --git a/site/downloads/avatica-go.md b/site/downloads/avatica-go.md
index 97ca7f0..555e4fd 100644
--- a/site/downloads/avatica-go.md
+++ b/site/downloads/avatica-go.md
@@ -51,7 +51,10 @@
{% endcomment %}{% capture d3 %}2018-03-01{% endcapture %}{% comment %}
{% endcomment %}{% capture d4 %}2018-06-01{% endcapture %}{% comment %}
{% endcomment %}{% capture d5 %}2018-09-11{% endcapture %}{% comment %}
-{% endcomment %}{% if d1 > d3 %}{% comment %}
+{% endcomment %}{% capture d6 %}2019-01-01{% endcapture %}{% comment %}
+{% endcomment %}{% if d1 > d6 %}{% comment %}
+{% endcomment %}{% assign digest = "sha512" %}{% comment %}
+{% endcomment %}{% elsif d1 > d3 %}{% comment %}
{% endcomment %}{% assign digest = "sha256" %}{% comment %}
{% endcomment %}{% elsif d1 > d2 %}{% comment %}
{% endcomment %}{% assign digest = "mds" %}{% comment %}
@@ -60,7 +63,7 @@
{% endcomment %}{% endif %}{% comment %}
{% endcomment %}<a href="{{ site.baseurl }}/docs/go_history.html#{{ post.tag }}">{{ post.version }}</a>{% comment %}
{% endcomment %} | {{ post.date | date_to_string }}{% comment %}
-{% endcomment %} | <a href="https://github.com/apache/calcite-avatica-go/commit/{{ post.sha }}">{{ post.sha }}</a>{% comment %}
+{% endcomment %} | {{ post.sha }}{% comment %}
{% endcomment %}{% if d1 < d5 %}{% comment %}
{% endcomment %} | <a href="{{ p }}/{{ f }}.tar.gz{{ q }}">tar</a>{% comment %}
{% endcomment %} (<a href="{{ d }}/calcite/{{ v }}/{{ f }}.tar.gz.{{ digest }}">{{ digest }}</a>{% comment %}
