Neworder

Functional changes

- add `StateGrid` class to domains

Examples

- convert Schelling example to use `StateGrid`
- add Conway's game of life example that uses `StateGrid`
- minor corrections to documentation
- docker container now installs neworder from package repo

Internal

- add lint (flake8) and config

Release to coincide with publication in the [_Journal of Open Source Software_](https://joss.theoj.org/)

Breaking changes

- `Model.timeline` and `Model.mc` are now class attributes where they were previously methods. (Change e.g. `model.mc().ustream(10)` to `model.mc.ustream(10)`)

Functional changes

- Add initial spatial domain support (`neworder.Domain`, `neworder.Space`):
- continuous rectangular domain in _n_ dimensions
- domain edges can be wrapped, contrained, mirrored or unbounded
- calculate positions, distances, proximity and movement for points in the domain
- New example using the domain functionality: boids flocking
- Migrate existing examples to use new domain functionality, where appropriate
- Fixes for wolf-sheep predation example

Other

- Various minor improvements resulting from JOSS reviewer comments.

Internals

- add a virtual clone method to `Timeline`, simplifying model construction.
- migration of most CI builds to github workflows.

Examples

- new: 3d N-body simulation
- new: wolf-sheep predation model
- fixed interactive figures (for matplotlib 3.4)

Internal improvements

- refactor package to support multiple submodules in future releases - allows for mixed python and C++ implementations
- enabled test coverage (codecov.io)

Breaking changes

- The function `neworder.version()` has been removed and replaced with the more standard `neworder.__version__`

**no functional change**
Bugfixes
- fix issue where `CalendarTimeline.dt()` always returned 0.0 for open-ended timelines

Breaking changes

- Calling the Model's `checkpoint` method during model run is no longer supported.
- The Model's `checkpoint` method has been renamed `finalise` and is called after the final timestep.

New features

- Monte-Carlo: added Poisson counts function
- Timeline: added open-ended linear timeline
- Timeline: added open-ended calendar timeline

Internal improvements

- Monte-Carlo: improved input parameter validation
- make global state parameters atomic
- consolidated CI builds: moved travis builds to appveyor
- examples code tar/zip files now versioned

This release purely addresses a build configuration issue with conda-forge. Functionally identical to 0.1.0