Analysis Wavelet Transform

[JessWhitney]

Adds the analysis transform (corresponding to issue #11) to s2wav. The original C code used for reference can be found here.

• Adds module to the init file
• Adds core code to 'analysis.py'
• Doesn't include any 'manual' or 'real' functions, only the core transform

[codecov-commenter]

Codecov Report

:exclamation: No coverage uploaded for pull request base (main@b5e537a). Click here to learn what that means. Patch has no changes to coverable lines.

Additional details and impacted files

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[JessWhitney]

Would you like me to wait for @alicjapolanska to take a look before merging, or merge now?

[CosmoMatt]

@JessWhitney probably best to just merge this in so we can be working on other moving parts! (for instance a vectorised version)