Isotropic and other feedback modes
Introduces changes from @chaikin in COLIBRE to the main code:
- Add a ray structure to uniformly sample directions around stars and BHs.
- Add 4 modes of feedback for SNII and AGN respectively: random (as now), isotropic, min distance and min density.
- Add the switch for deterministic / stochastic feedback mode for AGN.
- Rename some of the EAGLE AGN parameters for consistency.
- Update the EAGLE parameter files to use min-distance feedback throughout.
Edited by Matthieu Schaller