Bump nokogiri to address CVE-2017-15412
Bump nokogiri to address CVE-2017-15412

As reported by `bundler-audit`:

> Name: nokogiri
> Version: 1.8.1
> Advisory: CVE-2017-15412
> Criticality: Unknown
> URL: https://github.com/sparklemotion/nokogiri/issues/1714
> Title: Nokogiri gem, via libxml, is affected by DoS vulnerabilities
> Solution: upgrade to >= 1.8.2

jeroenj/stringer,swanson/stringer,nibble/stringer,dperson/stringer,jqr/stringer,Koronen/stringer,dperson/stringer,jeroenj/stringer,jeroenj/stringer,Koronen/stringer,swanson/stringer,swanson/stringer,geemus/stringer,geemus/stringer,nibble/stringer,nibble/stringer,jqr/stringer,Koronen/stringer,geemus/stringer,jqr/stringer,swanson/stringer,dperson/stringer,geemus/stringer,Koronen/stringer,dperson/stringer,nibble/stringer,jqr/stringer,jeroenj/stringer