Add periodic reparameterisation

[mj-will]

I recently realised that the time_jitter used in the time marginalisation for CBC signals in bilby is actually a periodic parameter (see here). This prompted me to add a generic reparameterisation for parameters that aren't periodic on [0, pi] or [0, 2pi].

The scale for generic periodic parameters is set as 2pi / angle_prior_range, for example for a parameter that is periodic on [-1, 1] the scale should be pi. This behaviour is enabled by setting scale=None.

Bug fix
This PR also fixes a minor bug in all reparameterisations when parameters=<some list>: the list is not copied to changes to the parameters made in the reparameterisation will be reflect in the original list. This could lead to unexpected behaviour if that list is used in other parts of the code.

[codecov-commenter]

Codecov Report

Merging #127 (ca977b1) into main (bc3eec0) will increase coverage by 0.03%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #127      +/-   ##
==========================================
+ Coverage   95.00%   95.03%   +0.03%     
==========================================
  Files          39       39              
  Lines        3626     3629       +3     
==========================================
+ Hits         3445     3449       +4     
+ Misses        181      180       -1     

Flag	Coverage Δ
unittests	95.03% <100.00%> (+0.03%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
nessai/reparameterisations.py	91.56% <100.00%> (+0.21%)	⬆️

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