This demo illustrates:

* How to define some of the different built-in meshes in DOLFIN

Problem definition
------------------

The demo focuses on the built-in meshes. We will look at the following
meshes:

* :py:class:`UnitIntervalMesh <dolfin.cpp.mesh.UnitIntervalMesh>`
* :py:class:`UnitSquareMesh <dolfin.cpp.mesh.UnitSquareMesh>`
* :py:class:`RectangleMesh <dolfin.cpp.mesh.RectangleMesh>`
* :py:class:`UnitCubeMesh <dolfin.cpp.mesh.UnitCubeMesh>`
* :py:class:`BoxMesh <dolfin.cpp.mesh.BoxMesh>`
