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, 24 deletions

diff --git a/vendor/golang.org/x/sys/unix/dev_darwin.go b/vendor/golang.org/x/sys/unix/dev_darwin.go
deleted file mode 100644
index 8d1dc0f..0000000
--- a/vendor/golang.org/x/sys/unix/dev_darwin.go
+++ /dev/null
@@ -1,24 +0,0 @@
-// Copyright 2017 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.
-
-// Functions to access/create device major and minor numbers matching the
-// encoding used in Darwin's sys/types.h header.
-
-package unix
-
-// Major returns the major component of a Darwin device number.
-func Major(dev uint64) uint32 {
-	return uint32((dev >> 24) & 0xff)
-}
-
-// Minor returns the minor component of a Darwin device number.
-func Minor(dev uint64) uint32 {
-	return uint32(dev & 0xffffff)
-}
-
-// Mkdev returns a Darwin device number generated from the given major and minor
-// components.
-func Mkdev(major, minor uint32) uint64 {
-	return (uint64(major) << 24) | uint64(minor)
-}