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, 95 deletions

diff --git a/vendor/golang.org/x/sys/unix/openbsd_pledge.go b/vendor/golang.org/x/sys/unix/openbsd_pledge.go
deleted file mode 100644
index 11388e5..0000000
--- a/vendor/golang.org/x/sys/unix/openbsd_pledge.go
+++ /dev/null
@@ -1,95 +0,0 @@
-// Copyright 2016 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 openbsd
-// +build 386 amd64 arm
-
-package unix
-
-import (
-	"errors"
-	"fmt"
-	"strconv"
-	"syscall"
-	"unsafe"
-)
-
-const (
-	_SYS_PLEDGE = 108
-)
-
-// Pledge implements the pledge syscall.
-//
-// The pledge syscall does not accept execpromises on OpenBSD releases
-// before 6.3.
-//
-// execpromises must be empty when Pledge is called on OpenBSD
-// releases predating 6.3, otherwise an error will be returned.
-//
-// For more information see pledge(2).
-func Pledge(promises, execpromises string) error {
-	maj, min, err := majmin()
-	if err != nil {
-		return err
-	}
-
-	// If OpenBSD <= 5.9, pledge is not available.
-	if (maj == 5 && min != 9) || maj < 5 {
-		return fmt.Errorf("pledge syscall is not available on OpenBSD %d.%d", maj, min)
-	}
-
-	// If OpenBSD <= 6.2 and execpromises is not empty
-	// return an error - execpromises is not available before 6.3
-	if (maj < 6 || (maj == 6 && min <= 2)) && execpromises != "" {
-		return fmt.Errorf("cannot use execpromises on OpenBSD %d.%d", maj, min)
-	}
-
-	pptr, err := syscall.BytePtrFromString(promises)
-	if err != nil {
-		return err
-	}
-
-	// This variable will hold either a nil unsafe.Pointer or
-	// an unsafe.Pointer to a string (execpromises).
-	var expr unsafe.Pointer
-
-	// If we're running on OpenBSD > 6.2, pass execpromises to the syscall.
-	if maj > 6 || (maj == 6 && min > 2) {
-		exptr, err := syscall.BytePtrFromString(execpromises)
-		if err != nil {
-			return err
-		}
-		expr = unsafe.Pointer(exptr)
-	}
-
-	_, _, e := syscall.Syscall(_SYS_PLEDGE, uintptr(unsafe.Pointer(pptr)), uintptr(expr), 0)
-	if e != 0 {
-		return e
-	}
-
-	return nil
-}
-
-// majmin returns major and minor version number for an OpenBSD system.
-func majmin() (major int, minor int, err error) {
-	var v Utsname
-	err = Uname(&v)
-	if err != nil {
-		return
-	}
-
-	major, err = strconv.Atoi(string(v.Release[0]))
-	if err != nil {
-		err = errors.New("cannot parse major version number returned by uname")
-		return
-	}
-
-	minor, err = strconv.Atoi(string(v.Release[2]))
-	if err != nil {
-		err = errors.New("cannot parse minor version number returned by uname")
-		return
-	}
-
-	return
-}