Mgcpy

- Update sphinx docs
- Fix discretized p-value bug
- Fix zero p-value bug
- Add MGC/Dcorr Time Series
- Raised some package requirements to fix errors with called packages

- Refactor the mgcpy package structure
- Add Manova
- Fix two sample tests
- Add scripts for k sample test power curves
- Update sphinx docs

- Add FastDCorr
- Update FastMGC to latest and more stable code
- Update FastMGC and FastDCorr unit test
- Update MGC's Smoothing and Distance Transform functions
- Fix broken unit tests

- Fix setup.py to be able to build from source when wheel is not found
- Add MANIFEST.in to include Cython `*.pyx` files

- Port repo from `NeuroDataDesign` to `neurodata` org
- Assert dims of input matrices

Added
- Port [MGC](https://github.com/neurodata/mgc)/[FastMGC](https://github.com/neurodata/mgc-matlab) into the package, by [tpsatish95](https://github.com/tpsatish95)
- Port HHG, Pearson/RV/Cca, Spearman/Kendall into package and add data simulations, by [sampan501](https://github.com/sampan501)
- Port [dcorr/mcorr/mantel](https://github.com/neurodata/mgc-matlab), power estimation, and validate implementations, by [junhaobearxiong](https://github.com/junhaobearxiong)
- Port [MDMR](https://github.com/FCP-INDI/C-PAC/blob/master/CPAC/cwas/mdmr.pyx) into package by, [sundaysundya](https://github.com/sundaysundya)
- Implement Random Forest Independence Test by, [rguo123](https://github.com/rguo123) [not in `master` yet]
- Implement 2-sample tests into package by [ananyas713](https://github.com/ananyas713)