[SEBA-450] (part 1)

Refactoring, python3 compat, and tox tests on:

- xosconfig
- xosgenx
- xosutil

Eliminate use of yaml.load() which is unsafe, switch to yaml.safe_load()

More diagnostics during database migration

Change-Id: I0fae5782fca401603a7c4e4ec2b9269ad24bda97
diff --git a/lib/xos-genx/xosgenx/targets/link-graph.xtarget b/lib/xos-genx/xosgenx/targets/link-graph.xtarget
index 04c9dba..e455129 100644
--- a/lib/xos-genx/xosgenx/targets/link-graph.xtarget
+++ b/lib/xos-genx/xosgenx/targets/link-graph.xtarget
@@ -5,7 +5,7 @@
         {% for l in model.links -%}
             ["{{ l.peer }}", "{{ l.src_port }}", "{{ l.dst_port }}"]{% if not loop.last %},{% endif %}
         {%- endfor %}
-        {%- if model.rlinks %},{% endif %}        
+        {%- if model.rlinks %},{% endif %}
         {% for l in model.rlinks -%}
             ["{{ l.peer }}", "{{ l.src_port }}", "{{ l.dst_port }}"]{% if not loop.last %},{% endif %}
         {%- endfor %}