NiBetaSeries: task related correlations in fMRI

## Release Notes

Thanks to @PeerHerholz and @njvack for their contributions on this release.
Special thanks to @snastase for being a great reviewer and improving the project
overall.
This release is special because it will be published in the
Journal of Open Source Software (JOSS).
One condition of this is that the authors on the paper be the only authors in the zenodo file.
I will modify the authors listed on the zenodo file for this release,
but I will add all contributors back on for the subsequent release.

## CHANGES
* [REL] v0.3.0 release (#181) @jdkent
* [DOC] edit joss paper for spelling/grammar (#180) @jdkent
* [ENH] reduce focus on parcellations (#179) @jdkent
* [FIX] generalized -> general linear model description (#178) @jdkent
* [FIX] Add math (#177) @jdkent
* [FIX] remove .git from the binder url (#175) @jdkent
* [FIX] add pypiwin32 as conditional dependency (#173) @jdkent
* [FIX] add readthedocs config file (#174) @jdkent
* [DOC] Minor changes to documentation text (#163) @snastase
* [MAINT] fix tagging/pushing docker images (#160) @jdkent
* [FIX] binder ci triggers (#159) @jdkent
* [ENH] add binder (#158) @jdkent
* [MAINT] Change Install Strategy (#157) @jdkent
* [DOC] Clarify Documentation (#156) @jdkent
* [FIX] Only hyphens for commandline parameters (#155) @jdkent
* [DOC] add concrete example of nibs (#154) @jdkent
* [DOC] add references (#153) @jdkent
* [MAINT] build docs on circleci (#152) @jdkent
* [MAINT] temporary fix to dockerfile (#150) @jdkent
* [MAINT] require python3 (#147) @jdkent
* [ENH] add visualizations (#148) @jdkent
* [ENH] Add Docker and Singularity Support (#140) @PeerHerholz
* [DOC] edit docs (#142) @jdkent
* [DOC] Tiny tweak to README (#141) @njvack
* [WIP] JOSS Paper (#122) @jdkent