Fracdiff

* ENH: Accept pandas.Dataframe in FracdiffStat (close 64) (65)

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* DOC: Update README.md (54)

* DOC: Elaborate docs (close 43) (56)

* ENH: [`torch.fdiff`](https://fracdiff.github.io/fracdiff/): A functional that extends [`torch.diff`](https://pytorch.org/docs/stable/generated/torch.diff.html) to fractional differentiation. (close #47) (49)
* ENH: [`torch.Fracdiff`](https://fracdiff.github.io/fracdiff/): A module that computes fractional differentiation. (close #47) (49)

* GITHUB: Fix GitHub Actions (44)

* DOC: Add link to GitHub (close 40) (42)

* DOC: Organize examples (35)

* DOC: Update Documentation

* GITHUB: Create GitHub Action to bump version (close 26) (28)

* GITHUB: Create `CONTRIBUTING.md` (29)

* DOC: Create Sphinx Documentation (30)