Added copyright information to footer
diff --git a/src/site/doxy/Doxyfile.in b/src/site/doxy/Doxyfile.in
index 1a468ce..9de7315 100644
--- a/src/site/doxy/Doxyfile.in
+++ b/src/site/doxy/Doxyfile.in
@@ -1184,7 +1184,7 @@
 # that doxygen normally uses.
 # This tag requires that the tag GENERATE_HTML is set to YES.
 
-HTML_FOOTER            =
+HTML_FOOTER            = ${CMAKE_SOURCE_DIR}/src/site/doxy/footer.html
 
 # The HTML_STYLESHEET tag can be used to specify a user-defined cascading style
 # sheet that is used by each HTML page. It can be used to fine-tune the look of
@@ -1209,7 +1209,7 @@
 # list). For an example see the documentation.
 # This tag requires that the tag GENERATE_HTML is set to YES.
 
-HTML_EXTRA_STYLESHEET  =
+HTML_EXTRA_STYLESHEET  = ${CMAKE_SOURCE_DIR}/src/site/doxy/customdoxygen.css
 
 # The HTML_EXTRA_FILES tag can be used to specify one or more extra images or
 # other source files which should be copied to the HTML output directory. Note
diff --git a/src/site/doxy/customdoxygen.css b/src/site/doxy/customdoxygen.css
new file mode 100644
index 0000000..e19beb6
--- /dev/null
+++ b/src/site/doxy/customdoxygen.css
@@ -0,0 +1,15 @@
+.navpath li.center
+{
+        list-style-type:none;
+        float:none;
+        padding-left:10px;
+        padding-right:10px;
+        background-image:none;
+        background-repeat:no-repeat;
+        background-position:right;
+        color:#364D7C;
+        font-size: 8pt;
+	line-height: 100%;
+        text-align: center;
+}
+
diff --git a/src/site/doxy/footer.html b/src/site/doxy/footer.html
new file mode 100644
index 0000000..2639b9a
--- /dev/null
+++ b/src/site/doxy/footer.html
@@ -0,0 +1,25 @@
+<!-- HTML footer for doxygen 1.8.13-->
+<!-- start footer part -->
+<!--BEGIN GENERATE_TREEVIEW-->
+<div id="nav-path" class="navpath"><!-- id is needed for treeview function! -->
+  <ul>
+    $navpath
+    <li class="footer">$generatedby
+    <a href="http://www.doxygen.org/index.html">
+    <img class="footer" src="$relpath^doxygen.png" alt="doxygen"/></a> $doxygenversion </li>
+    <li class="center">
+Copyright &copy; 2003-2020 <a href="https://www.apache.org/">Apache Software Foundation</a>. All Rights Reserved. <br/>
+Apache Logging, Apache Log4j, Log4j, Apache, the Apache feather logo, and the Apache Logging project logo are trademarks of The Apache Software Foundation.
+    </li>
+  </ul>
+</div>
+<!--END GENERATE_TREEVIEW-->
+<!--BEGIN !GENERATE_TREEVIEW-->
+<hr class="footer"/><address class="footer"><small>
+$generatedby &#160;<a href="http://www.doxygen.org/index.html">
+<img class="footer" src="$relpath^doxygen.png" alt="doxygen"/>
+</a> $doxygenversion
+</small></address>
+<!--END !GENERATE_TREEVIEW-->
+</body>
+</html>