chore(deps): update golang.org/x/sys commit hash to 4d1cda0 (#129)

Author: renovate[bot]

go.mod

@@ -5,5 +5,5 @@ require (
 	github.com/google/zoekt v0.0.0-20181210185712-6051a18956be
 	golang.org/x/net v0.0.0-20181207155508-610586996380
 	golang.org/x/sync v0.0.0-20181108010431-42b317875d0f // indirect
-	golang.org/x/sys v0.0.0-20181213155520-586ba8c9bb14 // indirect
+	golang.org/x/sys v0.0.0-20181213201944-4d1cda033e06 // indirect
 )

go.sum

@@ -57,6 +57,7 @@ golang.org/x/sys v0.0.0-20181211164050-7da8ea5c8182/go.mod h1:STP8DvDyc/dI5b8T5h
 golang.org/x/sys v0.0.0-20181212124545-b05ddf57801d/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20181213095516-73d4af5aa059/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20181213155520-586ba8c9bb14/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20181213201944-4d1cda033e06/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 google.golang.org/appengine v1.3.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=