Add transliteration option.

.gitignore

@@ -4,4 +4,6 @@ wiki
 *sublime-*
 coverage
 /.idea
-package-lock.json
+/package-lock.json
+/.npmrc
+/.vscode/settings.json

.npmignore

@@ -5,3 +5,4 @@ test
 wiki
 coverage
 .travis.yml
+/.npmrc

README.md

@@ -10,6 +10,7 @@
  * In-browser usage via [Browserify](https://github.com/substack/node-browserify) (~180k gzip compressed with Buffer shim included).
  * Typescript [type definition file](https://github.com/ashtuchkin/iconv-lite/blob/master/lib/index.d.ts) included.
  * React Native is supported (need to explicitly `npm install` two more modules: `buffer` and `stream`).
+ * Transliteration option is available when either [unidecode-plus](https://www.npmjs.com/package/unidecode-plus) or [unidecode](https://www.npmjs.com/package/unidecode) are added to your project
  * License: MIT.
 
 [![NPM Stats](https://nodei.co/npm/iconv-lite.png)](https://npmjs.org/package/iconv-lite/)  
@@ -30,7 +31,10 @@ str = iconv.decode(Buffer.from([0x68, 0x65, 0x6c, 0x6c, 0x6f]), 'win1251');
 buf = iconv.encode("Sample input string", 'win1251');
 
 // Check if encoding is supported
-iconv.encodingExists("us-ascii")
+iconv.encodingExists("us-ascii");
+
+// Convert from js string to an encoded buffer, keeping accented characters like "é", but transliterating Chinese.
+buf2 = iconv.encode("Café 北京", 'iso-8859-1', { transliterate: true });
 ```
 
 ### Streaming API (Node v0.10+)
@@ -143,11 +147,38 @@ This library supports UTF-32LE, UTF-32BE and UTF-32 encodings. Like the UTF-16 e
  * The default of UTF-32LE can be overridden with the `defaultEncoding: 'utf-32be'` option. Strips BOM unless `stripBOM: false`.
  * Encoding: uses UTF-32LE and writes BOM by default. Use `addBOM: false` to override. (`defaultEncoding: 'utf-32be'` can also be used here to change encoding.)
 
+## Transliteration
+
+If either [unidecode-plus](https://www.npmjs.com/package/unidecode-plus) or [unidecode](https://www.npmjs.com/package/unidecode) are added to your project ("`npm install unidecode-plus`" or "`npm install unidecode`"), the option will be available to transliterate characters which are not available in a particular encoding. The transliterations are always plain ASCII characters, but unlike using unidecode directly (which will convert *all* non-ASCII characters into transliterations), transliterations done using iconv will only transliterate characters which are not available in the target character encoding.
+
+In this example:
+```
+buf = iconv.encode("Café 北京", 'iso-8859-1', { transliterate: true });
+```
+The output is `<Buffer 43 61 66 e9 20 42 65 69 20 4a 69 6e 67 20>`. Converted back into ISO-8859-1 text, this is "Café Bei Jing ", preserving the accented "é", and only transliterating the Chinese characters.
+
+Transliteration to a string instead of a buffer can also be done directly, like this:
+```
+str = iconv.transliterate("Café 北京", 'iso-8859-1');
+```
+When encoding to create a buffer, the node-iconv style of requesting transliteration can also be used:
+```
+buf = iconv.encode("Café 北京", 'iso-8859-1//translit');
+```
+
+If you use `unidecode-plus` instead of `unidecode`, you get two additional transliteration options: `german`, and `smartSpacing`.
+
+The `german` option transliterates `Ä`, `ä`, `Ö`, `ö`, `Ü`, and `ü` to `AE`, `ae`, `OE`, `oe`, `UE`, and `ue`, respectively, instead of just removing the umlauts.
+
+The `smartSpacing` options improves the formatting of transliterated text, removing some unnecessary spaces, and adding others for clarity. For example, "Café 北京, 鞋 size 10½" becomes "Cafe Bei Jing, Xie size 10 1/2" using `smartSpacing`. Without it, you get "Cafe Bei Jing , Xie  size 101/2". (See the [unidecode-plus site](https://github.com/kshetline/unidecode-plus/blob/master/README.md) for more detail.)
+
+Please take note that transliteration only affects encoding, not decoding.
+
 ## Other notes
 
-When decoding, be sure to supply a Buffer to decode() method, otherwise [bad things usually happen](https://github.com/ashtuchkin/iconv-lite/wiki/Use-Buffers-when-decoding).  
-Untranslatable characters are set to � or ?. No transliteration is currently supported.  
-Node versions 0.10.31 and 0.11.13 are buggy, don't use them (see #65, #77).  
+* When decoding, be sure to supply a Buffer to decode() method, otherwise [bad things usually happen](https://github.com/ashtuchkin/iconv-lite/wiki/Use-Buffers-when-decoding).
+* Untranslatable characters are set to � or ? unless using transliteration.
+* Node versions 0.10.31 and 0.11.13 are buggy, don't use them (see #65, #77).  
 
 ## Testing