Update Travis, README, and setup.py

[mwaskom]

• Add test coverage reports through codecov
• Use conda-forge to get everything through conda
• Remove vestigial testing data
• Cleaner and updated setup.py
• Add badges to the README
• Update README and license text
• Work around [ENH] update for networkx dev version (should fix #2159) nipy/nipype#2171

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@310f5cf). Click here to learn what that means.
The diff coverage is 100%.

@@            Coverage Diff            @@
##             master     #144   +/-   ##
=========================================
  Coverage          ?   98.05%           
=========================================
  Files             ?       18           
  Lines             ?     3442           
  Branches          ?        0           
=========================================
  Hits              ?     3375           
  Misses            ?       67           
  Partials          ?        0

Impacted Files	Coverage Δ
lyman/__init__.py	100% <100%> (ø)

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