Remove Python3.4 And Add Python3.8

[helloqiu]

close #507

[codecov]

Codecov Report

Merging #508 into master will increase coverage by 0.09%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #508      +/-   ##
==========================================
+ Coverage   90.46%   90.55%   +0.09%     
==========================================
  Files          28       28              
  Lines        1437     1451      +14     
==========================================
+ Hits         1300     1314      +14     
  Misses        137      137

Impacted Files	Coverage Δ
werobot/messages/messages.py	100% <0%> (ø)	⬆️
werobot/contrib/django.py	100% <0%> (ø)	⬆️
werobot/utils.py	100% <0%> (ø)	⬆️
werobot/replies.py	100% <0%> (ø)	⬆️
werobot/client.py	98.07% <0%> (+0.03%)	⬆️
werobot/robot.py	87.54% <0%> (+0.21%)	⬆️

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[helloqiu]

tornadoweb/tornado#2608

[TravisBuddy]

Hey @helloqiu,
Your changes look good to me!

View build log

TravisBuddy Request Identifier: c3171200-0801-11ea-a7d8-2f45f8a3b8c0