Flavio

This release fixes a bug that raised an error on import on Python 3.4 (thanks to Joel Jones-Perez for pointing that out!)

In this release, the following new processes have been added:
- Branching ratios of the **inclusive radiative decays** B->X(d,s)gamma. Thanks to Mikołaj Misiak for discussions and numerical results needed to implement the NNLO SM contributions ([1503.01789](https://arxiv.org/abs/1503.01789) and references therein)! See the comments on [implementation details](http://flav-io.github.io/docs/physics.html#bto-xqgamma).
- More **lepton flavour violating** decays:
- B->Kll' and B->pill' (using [1506.03970](https://arxiv.org/abs/1506.03970))
- B->ll' (using [1602.00881](https://arxiv.org/abs/1602.00881))

Furthermore the **meson bag parameters** have been updated to v2 of [1602.03560](https://arxiv.org/abs/1602.03560) - this is a significant change compared to v1 used previously!

(Version number skipped - forgot to increment `_version.py`)

This is a major new release.

**New physics features:**
- The B->V form factors now use the updated numerics of version 2 of [arXiv:1503.05534](https://arxiv.org/abs/1503.05534). (Thanks in particular to Roman Zwicky.)
- subleading hadronic uncertainties are now included in B->K\* gamma decays consistently with B->K*ll (thanks to Ayan Paul for discussions)

**New processes:**
- B0->omega l nu

**New code features:**
- New function `flavio.sm_covariance` to get the theoretical covariance matrix (squared errors and correlations) within the Standard Model of a list of observables

**Bugs fixed:**
- A missing factor of 1/2 in B0->rho0nunu and B0->pi0nunu added

For a full list of changes, have a look at the [commit log](https://github.com/flav-io/flavio/commits/master).

In this new release, branching ratios and angular observables of the decays B_s->phi l l have been added. The implementation takes into account the sizable width difference between the two B_s mass eigenstates. The observables correspond to the time-averaged ones measured at hadron colliders like the LHC.

The B_s->phi form factors are based on [arXiv:1503.05534](https://arxiv.org/abs/1503.05534), the mixing formalism on [arXiv:1502.05509](https://arxiv.org/abs/1502.05509). Thanks to Javier Virto for discussions and cross-checks!

This release adds a number of functions to perform Bayesian fits of parameters and/or Wilson coefficients to experimental data. This functionality is to be considered experimental and still has to be added to the documentation.

Furthermore, the alternative observables P_1,2,3 in B->Vll decays have been added.