More small changes

More small changes to the docs.

1. Better landing page.
2. Minor tweaks to the side bar.
3. Reference to more example code.
4. Local MathJax references.

Change-Id: I39b9436dc2803732a875bbbee7f15802c4934031

docs/source/tutorial.rst

@@ -559,3 +559,30 @@ solvers, robust loss functions and local parameterizations see
 .. rubric:: Footnotes
 
 .. [#f5] The full source code for this example can be found in ``examples/simple_bundle_adjuster.cc``.
+
+
+Other Examples
+==============
+
+Besides the examples in this chapter, the  `example
+<https://ceres-solver.googlesource.com/ceres-solver/+/master/examples/>`_
+directory contains a number of other examples:
+
+#. `circle_fit.cc
+   <https://ceres-solver.googlesource.com/ceres-solver/+/master/examples/circle_fit.cc>`_
+   shows how to fit data to a circle.
+
+#. `nist.cc
+   <https://ceres-solver.googlesource.com/ceres-solver/+/master/examples/nist.cc>`_
+   implements and attempts to solves the `NIST
+   <http://www.itl.nist.gov/div898/strd/nls/nls_main.shtm>`_
+   non-linear regression problems.
+
+#. `denoising.cc
+   <https://ceres-solver.googlesource.com/ceres-solver/+/master/examples/denoising.cc>`_
+   implements image denoising using the `Fields of Experts
+   <http://www.gris.informatik.tu-darmstadt.de/~sroth/research/foe/index.html>`_
+   model.
+
+
+