[Releng] Improve the documentation for product builds to focus first on
Tycho 2.3
diff --git a/content/documentation.php b/content/documentation.php
index 18dccd9..bdc188c 100644
--- a/content/documentation.php
+++ b/content/documentation.php
@@ -50,18 +50,36 @@
 and naturally you can choose the specific JRE most suitable for the needs and size constraints of your specific product, e.g.,
 </p>
 <blockquote>
-<a href="https://download.eclipse.org/justj/jres/14/updates/nightly/latest/">https://download.eclipse.org/justj/jres/14/updates/nightly/latest</a>
+<a href="https://download.eclipse.org/justj/jres/15/updates/release/latest">https://download.eclipse.org/justj/jres/15/updates/release/latest</a>
 </blockquote>
 <p>
 There is a <a href="https://www.eclipse.org/forums/index.php/t/1104206/">forum thread</a> 
 and a <a href="https://www.eclipse.org/lists/justj-dev/msg00003.html">mailing list thread</a> recording the experience of others who have experimented with this.
+The <a href="https://www.eclipse.org/forums/index.php/t/1107858/">most recent thread</a> describes how best to get this working with Tycho 2.3.0.
+The JustJ p2 repositories include additional installable units that can be used directly as an execution environment, e.g., like this:
+</p>
+<pre>
+  &lt;plugin>
+     &lt;groupId>org.eclipse.tycho&lt;/groupId>
+     &lt;artifactId>target-platform-configuration&lt;/artifactId>
+     &lt;version>${tycho-version}&lt;/version>
+     &lt;configuration>
+        <b style="color: DarkOliveGreen;">&lt;executionEnvironment>org.eclipse.justj.openjdk.hotspot.jre.full-15&lt;/executionEnvironment></b>
+     &lt;/configuration>
+  &lt;/plugin>
+</pre>
+<p>
+There is one such <code>a.jre.*</code> installable unit for each JRE variant and it provides the execution environment capabilities and, most importly, exactly the actual the java package capabilities of that JRE.
+<p>
+
+</p>
 The Tycho/Maven build must use Tycho 1.7.0 or higher, otherwise the build will fail with a <code>NullPointerException</code>.
 The JustJ JREs have explicit negative requirements to exclude <code>a.jre</code> and <code>a.jre.javase</code> from consideration during resolution;
 this is to ensure that only the actual executation environments and Java packages provided by the real JRE are used for resolution.
-Tycho currently has problems dealing with this but <a href="https://www.eclipse.org/lists/tycho-user/msg08567.html">work is being done</a> to address that.
+Older versions of Tycho have problems dealing with this but <a href="https://www.eclipse.org/lists/tycho-user/msg08567.html">work has been done</a> to address that.
 </p>
 <p>
-In the meantime, one must either 
+One approach for older versions is to either 
 <b style="color: DarkSlateBlue;">disable</b> the use of the executation enviroment constraints during resolution,
 or <b style="color: DarkOliveGreen;">disable</b> the negative requirements themselves:
 </p>
@@ -106,23 +124,6 @@
 </p>
 
 <p>
-To avoid such problems, the JustJ p2 repositories now include additional installable units that can be used directly as an execution environment, e.g., like this:
-<p>
-<pre>
-  &lt;plugin>
-     &lt;groupId>org.eclipse.tycho&lt;/groupId>
-     &lt;artifactId>target-platform-configuration&lt;/artifactId>
-     &lt;version>${tycho-version}&lt;/version>
-     &lt;configuration>
-        <b style="color: DarkOliveGreen;">&lt;executionEnvironmentDefault>org.eclipse.justj.openjdk.hotspot.jre.full-14&lt;/executionEnvironmentDefault></b>
-     &lt;/configuration>
-  &lt;/plugin>
-</pre>
-<p>
-There is one such <code>a.jre.*</code> installable unit for each JRE variant and it provides the execution environment capabilities and, most importly, exactly the actual the java package capabilities of that JRE.
-<p>
-
-<p>
 Oomph has a complex and complete example of how to design a build to use the JustJ JREs.
 In this case the build produces both a product without a JRE as well as one with a JRE for maximum flexibility.
 See <a href="https://git.eclipse.org/c/oomph/org.eclipse.oomph.git/tree/products/org.eclipse.oomph.setup.installer.product">Oomph's Git repository</a> for details