Add unreleased libraries.

doc/libraries.xml

@@ -427,6 +427,18 @@
     <category>Domain</category>
     <category>System</category>
   </library>
+  <library>
+    <key>chrono/stopwatch</key>
+    <module>chrono</module>
+    <boost-version></boost-version>
+    <update-version>1.56.0</update-version>
+    <name>Chrono.Stopwatch</name>
+    <authors>Vicente J. Botet Escriba</authors>
+    <maintainers>Vicente J. Botet Escriba &lt;vicente.botet -at- wanadoo.fr&gt;</maintainers>
+    <description>Useful stopclocks and stopwatches utilities.</description>
+    <documentation>libs/chrono/stopwatches/</documentation>
+    <category>Domain</category>
+  </library>
   <library>
     <key>circular_buffer</key>
     <module>circular_buffer</module>
@@ -684,6 +696,27 @@
     <category>Domain</category>
     <category>System</category>
   </library>
+  <library>
+    <key>disjoint_sets</key>
+    <module>disjoint_sets</module>
+    <boost-version></boost-version>
+    <update-version>1.18.0</update-version>
+    <name>Disjoint Sets</name>
+    <authors>Jeremy Siek</authors>
+    <description>Class that provides disjoint sets operations with union by rank and path compression</description>
+    <documentation>libs/disjoint_sets/</documentation>
+  </library>
+  <library>
+    <key>disjoint_sets</key>
+    <module>disjoint_sets</module>
+    <boost-version></boost-version>
+    <update-version>1.34.0</update-version>
+    <name>Disjoint Sets</name>
+    <authors>Jeremy Siek</authors>
+    <maintainers>Jeremy Siek &lt;jeremy.siek -at- gmail.com&gt;</maintainers>
+    <description>Class that provides disjoint sets operations with union by rank and path compression</description>
+    <documentation>libs/disjoint_sets/</documentation>
+  </library>
   <library>
     <key>dynamic_bitset</key>
     <module>dynamic_bitset</module>