Compression tests

Closes #679

See merge request !1128

Use the P20 cooling tables for the Quick Lyman-alpha model

See merge request !1138

Update GEAR feedback

See merge request !1136

Store BH birth density and metallicity

See merge request !1135

Don't load ParticleIDs when using remap_ids

See merge request !1126

Fix mistake in the display of the constants at the start of a run. The reduced Hubble constant is 100km/s/Mpc not 1km/s/Mpc

Correct output of VELOCIraptorGroupIDs dataset in snapshots

Closes #691

See merge request !1116

Add fixed boundary particles to the code (boundary particles that will never have a velocity)

See merge request !1124

Add drift/kick/timestep function for sink

See merge request !1121

Remove string argument in some logger function

See merge request !1125

Implement logger writer

See merge request !1104

Allow black holes to be used when running with boundary particles and/or not receive gravity forces

See merge request !1123

Nonperiodic mpi

See merge request !1122

Set engine_max_proxy_centre_frac such that the max CoM displacement covers the entire diagonal size of a cell

This reverts commit 6e62b4f0.

Cleverer ids for particle splitting

See merge request !1106

Implement cell lock

See merge request !1120