Hippylib

----------------------------------------
- Alleviate boundary artifacts (inflation of marginal variance) in Bilaplacian-like priors
using Robin boundary conditions
- Allow the user to select different matplotlib colormaps in jupyter notebooks
- Buxfix in the acceptance ratio of the gpCN MCMC proposal

----------------------------------------
- Introduce capabilities for non-Gaussian Bayesian inference using Mark Chain Monte Carlo methods.
Kernels: mMALA, pCN, gpCN, IS. **Note: API subject to change**
- Support domain-decomposition parallelization (new parallel random number generator, and new randomized eigensolvers)
- The parameter, usually labeled `a`, throughout the library, has been renamed to `m`, for `model parameter`.
Interface changes:
- `PDEProblem.eval_da` --> `PDEProblem.evalGradientParameter`
- `Model.applyWua` --> `Model.applyWum`
- `Model.applyWau` --> `Model.applyWmu`
- `Model.applyRaa` --> `Model.applyWmm`
- `gda_tolerance` --> `gdm_tolerance` in the parameter list for Newton and QuasiNewton optimizers
- `gn_approx` --> `gass_newton_approx` as parameter in function to compute Hessian/linearization point in classes `Model`, `PDEProblem`, `Misfit`, `Qoi`, `ReducedQoi`
- Organize `hippylib` in subpackages
- Add `sphinx` documentation (thanks to **E. Khattatov** and **I. Ambartsumyan**)

----------------------------------------
- **Bugfix** in `PDEVariationalProblem.solveIncremental` for non self-adjoint models
- Add new estimator for the trace and diagonal of the prior covariance
using randomized eigendecomposition
- In all examples and tutorial, use enviromental variable `HIPPYLIB_BASE_DIR` (if defined)
to add `hIPPYlib` to `PYTHONPATH`

----------------------------------------
- Add support for `FEniCS 2017.2`

----------------------------------------
- Add support for `Python 3`
- Enchantments in `PDEVariationalProblem`: it now supports multiple Dirichlet
condition and vectorial/mixed function spaces
- Bugfix: Set the correct number of global rows, when targets points fall
outside the computational domain
- More extensive testing with `Travis` Integration

----------------------------------------
- Improve `hashdist` installation support
- Switch license to GPL-2
- Add support for `FEniCS 2017.1`