HPCC-8137 Add Programmers Guide to Set.

Fix HPCC-8137 Add Programmers Guide to
Reference Set included in Compiled Help
files, and Eclipse Help files.

Signed-off-by: g-pan <greg.panagiotatos@lexisnexis.com>

docs/ECLProgrammersGuide/PRG_Mods/PrG_Complex_ROXIE_Queries.xml

@@ -73,7 +73,7 @@ END;</programlisting>
     from the function that uses it.</para>
   </sect2>
 
-  <sect2 id="Keyed_Joins">
+  <sect2 id="PG_Keyed_Joins">
     <title>Keyed Joins</title>
 
     <para>Although the FETCH function was specifically designed for indexed

docs/ECLProgrammersGuide/PRG_Mods/PrG_Smart_Stepping.xml

@@ -4,7 +4,7 @@
 <sect1 id="Smart_Stepping">
   <title><emphasis role="bold">Smart Stepping</emphasis></title>
 
-  <sect2 id="Overview">
+  <sect2 id="PG_Overview">
     <title>Overview</title>
 
     <para>Smart Stepping is a set of indexing techniques that, taken together,

docs/ECLProgrammersGuide/PRG_Mods/PrG_Using_Group_Function.xml

@@ -85,7 +85,7 @@ OUTPUT(i2);
     the second.</para>
   </sect2>
 
-  <sect2 id="Performance_Considerations">
+  <sect2 id="PG_Performance_Considerations">
     <title>Performance Considerations</title>
 
     <para>There is also a major performance advantage to using the GROUP