Delete vendored code and update CI to Go 1.13 (#158)

As the Go community transitions to using the modules ecosystem,
we want to only support one way of managing dependencies.
So this change moves to only using Go modules for dependency management.

This means that our effective minimum Go version increases to Go 1.11.
To account for this, we also update:
  - the documentation
  - Makefile
  - CI scripts

1 files changed, 0 insertions, 25 deletions

diff --git a/vendor/golang.org/x/sys/unix/race0.go b/vendor/golang.org/x/sys/unix/race0.go
deleted file mode 100644
index ad02667..0000000
--- a/vendor/golang.org/x/sys/unix/race0.go
+++ /dev/null
@@ -1,25 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build aix darwin,!race linux,!race freebsd,!race netbsd openbsd solaris dragonfly
-
-package unix
-
-import (
-	"unsafe"
-)
-
-const raceenabled = false
-
-func raceAcquire(addr unsafe.Pointer) {
-}
-
-func raceReleaseMerge(addr unsafe.Pointer) {
-}
-
-func raceReadRange(addr unsafe.Pointer, len int) {
-}
-
-func raceWriteRange(addr unsafe.Pointer, len int) {
-}