Adding a class *LagrangeInterpolator* that interpolates a GenericFunction fast onto a Lagrange function space.
Changing order of arguments in interpolate and adding unittest to /test/unit/test.py
Adding dolfin_assert where appropriate and using const for STL iterators. Fixed conflict in unit/test.py
Fix Issue #300
Fix Issue #71.

SWIG does not handle shared_ptr and directors properly, hence we need to somethimes store a reference to an object in the Python wrappers.
Merge remote-tracking branch 'origin/garth/fix-issue-300'
Allow arbitrary shaped functions in errornorm with TensorFunctionSpace.

Fixes issue 180.

Also did some cleanup and future proofing by avoiding
passing mesh= to assemble.
Add warnings and deprecations in assemble* and Form.__init__.

In some combinations of input, assemble* has dangerous behaviour
modifying input arguments, which we now warn against.

A lot of arguments are due for removal and have been marked for deprecation.
Merge branch 'mikael/lagrange-interpolation'
Remove deprecated VariationalProblem (fixes Issue #239)
Remove deprecated functions from GenericDofMap (fixes Issue #202)
Remove deprecated UnitCircle{Mesh} (fixes Issue #201)
Remove UnitFoo meshes (fixes Issue #203)
Remove import of removed module 'variationalproblem'
Add IntervalMesh.h to dolfin_generation.h
Merge branch 'garth/fix-issue-201' into garth/fix-issue-203

Fix old code in book test.

Conflicts:
	dolfin/generation/dolfin_generation.h
	dolfin/swig/shared_ptr_classes.i
Use ugly double square brackets to fix MathJax problem (fixes Issue #163)

Problem is that MathJax does not support \llbracket and \rrbracket
Merge branch 'garth/fix-issue-203'
Merge branch 'garth/fix-issue-202'
Merge branch 'garth/fix-issue-239'