Adding various strain mapping algorithms

[mitis1]

What problem this PR addresses

This PR adds an implementation of the cepstral transform, template matching, and model fitting for strain mapping. The cepstral implementation is based on this paper by Padgett et al and the template matching is based on py4dstem's algorithm. Model fitting is a new method for calculating strain using a rendered diffraction pattern and fitting it to match the original.

The cepstral implementation is mainly in strain_autocorrelation.py file.
Disk detection is in bragg_vectors.py, bragg_vectors_visualization.py, and disk_detection.py.
Model fitting uses model_fitting.py and model_fitting_visualization.py. It also implements a base fitting model that can be used for implementations beyond strain mapping.

The PR also makes a strain class which calculates and saves the strain map using the results of any of the previous algorithms. It is implemented in strain.py and strain_visualizations.py

What should the reviewer(s) do

• Check the implementation of the various strain mapping algorithms.
• See if the strain class works for all the listed methods
• Run the test scripts and verify it works (the dataset is too big to attach so I can send it separately as needed)

model-fitting.ipynb
cepstral_mp.ipynb
cepstral.ipynb
disk-detection.ipynb