Update documentation

Address issue #66

Update documentation for ElasticFEModel to state the current version of the boundary conditions.
Add 3D elasticity model

Address issue #66

Add 3D elasticity model. Still needs significant work. It looks like
the solver for the 3D model may need to be different from the solver
for the 2D model.
Show 2D model works while 3D model does not

Address issue #66

The files elasticFEModel.py and elasticFEModel3D.py currently print
out the displacement fields in 2D (ElasticFEModel) and in 3D
(ElasticFE3DModel).  In both models, the displacement fields should
run from 0.0 to 3.0 in the x direction and be zero in the other
directions. The ElasticFEModel does give this results while the
Elastic3Dmodel doesn't.
Add baseElasticFEModel

Address issue #66
Address issue #71

Add BaseElasticFEModel as class to contain any overlap between 2D and
3D elasticity examples. Also change the API to take in the Young's
moduli and Poisson's ratios when the class is instantiated, and take in
only the microstructure for the predict method.
Merge ElasticFEmodel and ElasticFE3DModel and Update API

Fix issue #71
Address issue #66

Merge ElasticFEModel and ElasticFE3DModel to work for both 3D and 2D
microstructures. Update ElasticFEModel API to take in material
properties as arguments when it is instantiated. and pass only the
microstructure.  Changed the name of the predict method to
get_response, and now takes the microstructure as an argument rather
than the microstructure property array. Update doc tests with new
API. Make all helper methods underscore methods. Remove dx as an
argument for ElasticFEModel. Update tests with new API.
Create function to generate delta microstructure data

Address issue #66

Create make_elasticFEstrain_delta as a simple API to get delta
microstructures and strain fields. Changed class name from
ElasticFEModel to ElasticFESimulation.
Merge branch 'master' into issue66-3Dexample

Conflicts:
	pymks/elasticFEModel.py
Clean datasets module API docs

Address #66

API docs were messed up. Switched to using sphinxcontrib-napolean for
docstrings to clean them up.
Add function to generate strain from random microstructure

Address issue #66

Add function to generate strain fields from random
microstructures. Update documentation.
Update intro notebook

Address issue #71

Update intro notebook to include in updated API for elasticFESimulation as well as add more text to example how to use the MKSRegressionModel class.
Add macroscopic strain to make_elasticFEstrain functions

Address issue #71

Add macroscopic strain to make_elasticFEstrain functions to allow the
user to select the macroscopic strain used in the finite element
simulation.
Update text in intro notebook
Add and modify draw functions

Add draw_coeff function to generate plots of influence
coefficients. Add draw_strains to plot different strain fields from a
FE simulation. Change draw_strain to draw_strain_compare to compare
the difference in strain fields between FE and MKS.
Add elastic_2D notebook with updated ElasticFESimulation API

Address issue# 71
Address issue# 65

Add elastic_2D notebook with updated ElasticFESimulation API and
reserve the elastic notebook for the 3D example.
Change strain to macrostrain in ElasticFESimulation

Change the parameter name from strain to macrostrain to remove
ambiguity. Change path for loading ElasticFESimulation to import from
pymks.datasets instead of just pymks.
Change of plots in tools

Change color of plots made by draw tools in pymks.tools
Edit text in 2D elastic example
Change plot colors on intro
Rename elasticity notebook to elasticity_3D and update text

Fix issue #66

Rename elasticity notebook to elasticity_3D to distinguish from
2D. Update text in example.
Update EXAMPLES.rst file to include in notebook names

Address issue #66

Update EXAMPLES.rst file to include in notebook names elastic_2D and elastic_3D