add versioneer, add segdyn to docs, address a few issues

[knaaptime]

• resolves #301
• resolves #310
• resolves #77
• resolves #239

[codecov[bot]]

Codecov Report

Merging #312 (78df9c1) into master (3981425) will decrease coverage by 16.0%. The diff coverage is 46.5%.

@@            Coverage Diff            @@
##           master    #312      +/-   ##
=========================================
- Coverage    78.8%   62.8%   -16.0%     
=========================================
  Files          15      16       +1     
  Lines        1252    1601     +349     
=========================================
+ Hits          987    1006      +19     
- Misses        265     595     +330     

Impacted Files	Coverage Δ
geosnap/_version.py	40.7% <40.7%> (ø)
geosnap/_community.py	73.0% <66.7%> (-2.5%)	:arrow_down:
geosnap/analyze/dynamics.py	64.9% <78.6%> (-35.1%)	:arrow_down:
geosnap/analyze/analytics.py	85.9% <88.2%> (ø)
geosnap/__init__.py	100.0% <100.0%> (ø)
geosnap/_data.py	71.2% <100.0%> (-2.2%)	:arrow_down:
geosnap/harmonize/harmonize.py	87.2% <100.0%> (+0.3%)	:arrow_up:
geosnap/io/storage.py	28.1% <0.0%> (-64.4%)	:arrow_down:
... and 2 more