Update tocDefinitions.rst

Second fix in docs needed for https://github.com/Itseez/opencv_contrib/pull/70
http://www.build.opencv.org/buildbot/builders/precommit-contrib_docs/builds/277

doc/tutorials/definitions/tocDefinitions.rst

@@ -14,3 +14,4 @@
 .. |Author_MimmoC| unicode:: Mimmo U+0020 Cosenza
 .. |Author_BarisD| unicode:: Bar U+0131 U+015F U+0020 Evrim U+0020 Demir U+00F6 z
 .. |Author_DomenicoB| unicode:: Domenico U+0020 Daniele U+0020 Bloisi
+.. |Author_MarvinS| unicode:: Marvin U+0020 Smith