Sphinx and CMake, based on this example:
   http://ericscottbarr.com/blog/2012/03/sphinx-and-cmake-beautiful-documentation-for-c-projects/

The 'docs/CMakeLists.txt' file was deleted in this commit: 0abfb8f46f534b05413bb4d64b960d6fd0a9befb

Thanks to Arnaud Gelas, he has passed some links:
   https://github.com/InsightSoftwareConsortium/ITKExamples/blob/master/CMake/FindSphinx.cmake
   https://github.com/InsightSoftwareConsortium/ITKExamples/blob/master/CMakeLists.txt#L120-L154

Change-Id: Ic65e7f8ec5280d1e71a897a144417a21761c5553
diff --git a/cmake/FindSphinx.cmake b/cmake/FindSphinx.cmake
new file mode 100644
index 0000000..cd55bbe
--- /dev/null
+++ b/cmake/FindSphinx.cmake
@@ -0,0 +1,35 @@
+# Find the Sphinx documentation generator
+#
+# This modules defines
+#  SPHINX_EXECUTABLE
+#  SPHINX_FOUND
+
+FIND_PROGRAM(SPHINX_EXECUTABLE
+             NAMES sphinx-build
+             PATHS
+               /usr/bin
+               /usr/local/bin
+               /opt/local/bin
+             DOC "Sphinx documentation generator")
+
+IF (NOT SPHINX_EXECUTABLE)
+  SET(_Python_VERSIONS 2.7 2.6 2.5 2.4 2.3 2.2 2.1 2.0 1.6 1.5)
+
+  FOREACH (_version ${_Python_VERSIONS})
+    SET(_sphinx_NAMES sphinx-build-${_version})
+
+    FIND_PROGRAM(SPHINX_EXECUTABLE
+                 NAMES ${_sphinx_NAMES}
+                 PATHS
+                   /usr/bin
+                   /usr/local/bin
+                   /opt/loca/bin
+                 DOC "Sphinx documentation generator")
+  ENDFOREACH ()
+ENDIF ()
+
+INCLUDE(FindPackageHandleStandardArgs)
+
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(Sphinx DEFAULT_MSG SPHINX_EXECUTABLE)
+
+MARK_AS_ADVANCED(SPHINX_EXECUTABLE)