Update html2text lib to use the original repo (#8900)

vendor/github.com/ssor/bom/.travis.yml

@@ -0,0 +1,14 @@
+language: go
+go:
+  - tip
+  - 1.8
+  - 1.7
+  - 1.6
+  - 1.5
+  - 1.4
+  - 1.3
+  - 1.2
+notifications:
+  email:
+    on_success: change
+    on_failure: always

vendor/github.com/ssor/bom/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2017 Asher
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

vendor/github.com/ssor/bom/README.md

@@ -0,0 +1,23 @@
+# bom
+small tools for cleaning bom from byte array or reader
+
+
+## Installation
+
+```sh
+$ go get github.com/ssor/bom
+```
+
+## How to Use
+
+
+```
+	bs := []byte{bom0, bom1, bom2, 0x11}
+	result := CleanBom(bs)
+```
+
+```
+	bs := []byte{bom0, bom1, bom2, 0x11}
+	result := NewReaderWithoutBom(bytes.NewReader(bs))
+
+```

vendor/github.com/ssor/bom/bom.go

@@ -0,0 +1,34 @@
+package bom
+
+import (
+	"bytes"
+	"io"
+	"io/ioutil"
+)
+
+const (
+	bom0 = 0xef
+	bom1 = 0xbb
+	bom2 = 0xbf
+)
+
+// CleanBom returns b with the 3 byte BOM stripped off the front if it is present.
+// If the BOM is not present, then b is returned.
+func CleanBom(b []byte) []byte {
+	if len(b) >= 3 &&
+		b[0] == bom0 &&
+		b[1] == bom1 &&
+		b[2] == bom2 {
+		return b[3:]
+	}
+	return b
+}
+
+// NewReaderWithoutBom returns an io.Reader that will skip over initial UTF-8 byte order marks.
+func NewReaderWithoutBom(r io.Reader) (io.Reader, error) {
+	bs, err := ioutil.ReadAll(r)
+	if err != nil {
+		return nil, err
+	}
+	return bytes.NewReader(CleanBom(bs)), nil
+}