This commit fixes typo in README.md (Closes #151)

 -Finding the typo was harder than finding waldo
9 jobs for 151-ReadMeTypo in 2 minutes and 1 second (queued for 1 second)
Status Job ID Name Coverage
  Test
passed #3481
Go-py2.7

00:01:23

passed #3482
Go-py3.4

00:01:23

passed #3483
Go-py3.5

00:01:22

canceled #3497
Go-py3.6

00:00:25

failed #3488
Go-py3.6

00:01:05

failed #3484
Go-py3.6

00:01:18

failed #3486
Go-py3.6

00:01:04

failed #3487
Go-py3.6

00:01:03

 
  Lint
skipped #3485
Go-flake8