Add new action to infer a tabular resource schema

[aivuk]

Implement new action as described on #76.

• [x] New action logic
• [ ] Add tests

[codecov[bot]]

Codecov Report

Merging #82 (1c984dd) into master (1073c80) will decrease coverage by 0.72%. The diff coverage is 13.63%.

:exclamation: Current head 1c984dd differs from pull request most recent head 670d896. Consider uploading reports for the commit 670d896 to get more accurate results

@@            Coverage Diff             @@
##           master      #82      +/-   ##
==========================================
- Coverage   84.55%   83.82%   -0.73%     
==========================================
  Files          24       24              
  Lines        2117     2139      +22     
==========================================
+ Hits         1790     1793       +3     
- Misses        327      346      +19     

Impacted Files	Coverage Δ
ckanext/validation/logic.py	64.30% <9.52%> (-3.97%)	:arrow_down:
ckanext/validation/plugin/__init__.py	96.05% <100.00%> (+0.02%)	:arrow_up:

:mega: We’re building smart automated test selection to slash your CI/CD build times. Learn more

[aivuk]

Looks good so far @aivuk, I added some comments

BTW this coverage messages are really annoying. I guess they'll go away when you add tests but I'd be happy to turn them off, if you find how to do it

removed it for now