Deformer - Filter

[jatinkhilnani]

Low-, band- and high-pass filter deformer (#1)

[bmcfee]

@jatinkhilnani I didn't realize you were still working on this. Another student has also been working on this deformer, though her implementation may be pretty different from yours. Perhaps there's a way to combine them?

[jatinkhilnani]

Continued on it once PR #80 was merged, to include any further feedback (if any). Should have checked with you first.

Based on the PR #83, the implementation seems more exhaustive as I was not sure of the annotation impact. Two items that I see have to be considered though.

1. Handling of the cutoff parameter can be made concise and integrated
2. test_deformers.py has conflict since it does not have modifications from PR Clipping deformer & cosmetic fixes #80

Additional points.
3. I think the three methods for RandomFilter can be merged in one
4. LinearFilter implementation can be taken from this PR

There are benefits of combining the two implementations, should I coordinate with the author then? Please suggest, thanks!

[jatinkhilnani]

@bmcfee Should I proceed by taking code from PR #83 and making the suggested modifications along with LinearFilter implementation, or suggest otherwise.