Feature/plcontainer reorg (#9768)

* clarifying pg_upgrade note

* first edits

* edits for menu and content

* menu changes

* further funtion edits

* new file for config reference

* editing links and configuration file reference

* fixing references

* further link edits

* move of logging section

* arranging sections

* fixing references

* intro edits

* small edit

* small improvements

gpdb-doc/dita/analytics/analytics.ditamap

@@ -12,7 +12,13 @@
     <topicref href="postGIS.xml" navtitle="Geospatial Analytics" otherprops="pivotal" linking="none"/>
     <topicref href="text.xml" navtitle="Text Analytics and Search" otherprops="pivotal" linking="none"/>
     <topicref href="intro.xml" navtitle="Procedural Languages" linking="none">
-      <topicref href="pl_container.xml" navtitle="PL/Container" linking="none"/>
+    <topicref href="pl_container.xml" navtitle="PL/Container" linking="none">
+          <topicref href="pl_container.xml#about_pl_container" navtitle="About PL/Container Language Extension" linking="none"/>
+          <topicref href="pl_container.xml#topic3" navtitle="Install PL/Container" linking="none"/>
+          <topicref href="pl_container.xml#upgrade_plcontainer" navtitle="Upgrade PL/Container" linking="none"/>
+          <topicref href="pl_container.xml#uninstall_plcontainer" navtitle="Unistall PL/Container" linking="none"/>
+          <topicref href="pl_container.xml#topic_kds_plk_rbb" navtitle="PL/Container References" linking="none"/>
+          </topicref>
       <topicref href="pl_java.xml" linking="none"/>
       <topicref href="pl_perl.xml" linking="none"/>
       <topicref href="pl_sql.xml" linking="none"/>

gpdb-doc/dita/utility_guide/contrib-programs.xml

@@ -9,7 +9,7 @@
         installed:</p>
     <ul>
       <li><codeph><xref href="https://www.postgresql.org/docs/9.4/pgupgrade.html" scope="external"
-            format="html">pg_upgrade</xref></codeph> - Server program to upgrade a Greenplum
+            format="html">pg_upgrade</xref></codeph> - Server program to upgrade a Postgres
         Database server instance.<note><codeph>pg_upgrade</codeph> is not intended for direct use
         with Greenplum 6, but will be used by Greenplum upgrade utilities in a future
         release.</note></li>