Lmfit

- add AMPGO and basin-hopping global optimization methods.
- aborting a fit from the objective function now raises AbortFitException
- fit statistics are more uniformly calculated.
- the uncertainties package is now an external dependency, and an out-dated copy is no longer kept in lmfit.
- more exceptions when import matplotlib are now tolerated.
- many documentation fixes.

This release provides a few small but important changes compared to 0.9.8:

* asteval is now required as a separate install -- a copy is no longer included in lmfit. This makes it easier for asteval developments to happen independently from lmfit.
* the formatting of floating point numbers in the fit report is now better, fixing at least one bug where the values reported were truncated and incorrect.
* prefixes of Model components can be changed after the model is created.
* saving models and modelresults can now include user-specified data (as long as it can be converted to json!).