Eagerx-ode

Fix
* Graph refactor ([41](https://github.com/eager-dev/eagerx_ode/issues/41)) ([`e96ac66`](https://github.com/eager-dev/eagerx_ode/commit/e96ac668d9c84b083784fda9bb148910e450e20c))

Fix
* Update dependencies ([`aebceaf`](https://github.com/eager-dev/eagerx_ode/commit/aebceaf3734a09aba9071f2eebaddf03b9c9eb4d))
* Refactor bridge to engine ([`5250d06`](https://github.com/eager-dev/eagerx_ode/commit/5250d0693801290d11a8a66ac944a01bcae92a0e))
* Refactor initialize_spec ([`e44c466`](https://github.com/eager-dev/eagerx_ode/commit/e44c466bace045945c9ab8ad5b400989f1305c06))

Documentation
* Update bibtex typo ([`fd5c2be`](https://github.com/eager-dev/eagerx_ode/commit/fd5c2bee05c4551df615db86db3435d1b3b3b076))

Fix
* Bump flake8, eagerx, pytest ([`1ffd80f`](https://github.com/eager-dev/eagerx_ode/commit/1ffd80f9e98028d68efb1b8f194c82a6f9acd5d5))
* Refactor `is_reactive` to `sync` ([`095741e`](https://github.com/eager-dev/eagerx_ode/commit/095741e7b6fb004a5f044cc1353114b031909716))

Fix
* Add engine node for float32 observations ([`e9127cc`](https://github.com/eager-dev/eagerx_ode/commit/e9127cce4657a3c55b0712e584ddd471e902fac9))

Fix
* Dfun odeint ([`ec3edf9`](https://github.com/eager-dev/eagerx_ode/commit/ec3edf9d59943e4b8badf3a9918d2e010f29bb3a))