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, 38 deletions

diff --git a/vendor/golang.org/x/sys/cpu/cpu.go b/vendor/golang.org/x/sys/cpu/cpu.go
deleted file mode 100644
index 3d88f86..0000000
--- a/vendor/golang.org/x/sys/cpu/cpu.go
+++ /dev/null
@@ -1,38 +0,0 @@
-// Copyright 2018 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.
-
-// Package cpu implements processor feature detection for
-// various CPU architectures.
-package cpu
-
-// CacheLinePad is used to pad structs to avoid false sharing.
-type CacheLinePad struct{ _ [cacheLineSize]byte }
-
-// X86 contains the supported CPU features of the
-// current X86/AMD64 platform. If the current platform
-// is not X86/AMD64 then all feature flags are false.
-//
-// X86 is padded to avoid false sharing. Further the HasAVX
-// and HasAVX2 are only set if the OS supports XMM and YMM
-// registers in addition to the CPUID feature bit being set.
-var X86 struct {
-	_            CacheLinePad
-	HasAES       bool // AES hardware implementation (AES NI)
-	HasADX       bool // Multi-precision add-carry instruction extensions
-	HasAVX       bool // Advanced vector extension
-	HasAVX2      bool // Advanced vector extension 2
-	HasBMI1      bool // Bit manipulation instruction set 1
-	HasBMI2      bool // Bit manipulation instruction set 2
-	HasERMS      bool // Enhanced REP for MOVSB and STOSB
-	HasFMA       bool // Fused-multiply-add instructions
-	HasOSXSAVE   bool // OS supports XSAVE/XRESTOR for saving/restoring XMM registers.
-	HasPCLMULQDQ bool // PCLMULQDQ instruction - most often used for AES-GCM
-	HasPOPCNT    bool // Hamming weight instruction POPCNT.
-	HasSSE2      bool // Streaming SIMD extension 2 (always available on amd64)
-	HasSSE3      bool // Streaming SIMD extension 3
-	HasSSSE3     bool // Supplemental streaming SIMD extension 3
-	HasSSE41     bool // Streaming SIMD extension 4 and 4.1
-	HasSSE42     bool // Streaming SIMD extension 4 and 4.2
-	_            CacheLinePad
-}