doc fix for the example in the readme
A few fixes for v0.13
Merge pull request #12 from parroty/doc

doc fix for the example in the readme
Merge branch 'v0.13' of https://github.com/knewter/mock into v0.13
Updated the exenv version
Merge pull request #14 from jjh42/v0.13

V0.13
Merge branch 'master' of github.com:jjh42/mock