Myokit

- Small fixes to CellML validation.
- Fixed typo in units `becquerel`.
- Added `notanumber` and `infinity` to MathML parser.

- Removed `myo` script.
- Fixed EasyML issue for inf/tau variables used by more than one state.

- Added more import/export options to the IDE menu.
- Updated `component.code()` to always outout aliases in the same order.
- Added method to find Markov models in a Myokit model.
- Added method to convert Markov models to compact form.
- Added method to convert Markov models to full ODE form.
- LinearModel now converts to full ODE form.
- Added method `lib.guess.membrane_capacitance`.
- Added method `lib.guess.membrane_currents`.
- Added (experimental) EasyML export.
- Small bugfixes and documentation updates.
- Improved exception handling when evaluating a unit containing an invalid power.
- Made default script and protocol robust against incompatible units.
- Made CellML API `from_myokit_model` more robust against invalid units.

- Rewrote CellML import and export, with improved error handling and validation.
- CellML import now converts hardcoded stimulus equation to Myokit protocol.
- CellML export now converts Myokit protocol to hardcoded stimulus equation.
- CellML import now generates more approprate default scripts.
- CellML import now supports unit conversion between components.
- CellML export now infers units from RHS if no unit set.
- CellML import and export can now both handle Web Lab `oxmeta` annotations.
- Various changes and improvements to MathML parsing.
- Added missing `__iter__` to Model and VarOwner.
- The myokit.Name expression can now wrap objects other than myokit.Variable, allowing Myokit's expression system to be re-used for non-myokit expressions.
- Removed myokit.UnsupportedFunction.

- Added guessing module, with method to guess which variables (if any) represent the membrane potential and stimulus current.
- Fix for sundials development versions.
- Fixes for PySide2 support.

- Myokit is now released under a BSD 3-clause license
- Bugfix to `myokit step` command line tool.