Feature/add metrics

[caiyinqiong]

No description provided.

[codecov]

Codecov Report

Merging #132 into dev will decrease coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##              dev     #132      +/-   ##
==========================================
- Coverage   93.30%   93.28%   -0.02%     
==========================================
  Files         113      115       +2     
  Lines        4224     4275      +51     
==========================================
+ Hits         3941     3988      +47     
- Misses        283      287       +4     

Impacted Files	Coverage Δ
matchzoo/metrics/f1.py	95.45% <0.00%> (ø)
matchzoo/metrics/recall.py	90.90% <0.00%> (ø)

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