minor update to README

11 jobs for master in 5 minutes and 2 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
passed #392035
build:debian:jessie

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passed #392036
build:debian:stretch

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passed #392034
build:el7

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passed #392033
build:tarball

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  Test
passed #392042
docs

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passed #392043
syntax

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passed #392037
test:python2.7

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passed #392038
test:python3.4

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passed #392039
test:python3.5

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passed #392040
test:python3.6

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passed #392041
test:python3.7

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