Add unwrap tags documentation to other places (API, OPTIONS, README)

Author: nmielnik

API.md

@@ -399,12 +399,12 @@ _replace the current selection with html_
 
 2. _**options** (`Object`)_ _**OPTIONAL**_:
 
-  * Optional overrides for `cleanTags` and/or `cleanAttrs` for removing specific element types (`cleanTags`) or specific attributes (`cleanAttrs`) from the inserted HTML.  See [cleanTags](OPTIONS.md#cleantags) and [cleanAttrs](OPTIONS.md#cleanattrs) in OPTIONS.md for more information.
+  * Optional overrides for `cleanTags`, `unwrapTags`, and/or `cleanAttrs` for removing/unwrapping specific element types (`cleanTags`/`unwrapTags`),  or removing specific attributes (`cleanAttrs`) from the inserted HTML.  See [cleanTags](OPTIONS.md#cleantags), [unwrapTags](OPTIONS.md#unwraptags), and [cleanAttrs](OPTIONS.md#cleanattrs) in OPTIONS.md for more information.
 
 ##### Example
 
 ```js
-editor.pasteHTML('<p class="classy"><strong>Some Custom HTML</strong></p>', { cleanAttrs: ['class'], cleanTags: ['strong']});
+editor.pasteHTML('<p class="classy"><strong>Some Custom HTML</strong></p>', { cleanAttrs: ['class'], cleanTags: ['strong'], unwrapTags: ['em']});
 ```
 
 ***

OPTIONS.md

@@ -532,6 +532,7 @@ List of element tag names to remove during paste when __cleanPastedHTML__ is `tr
 
 List of element tag names to unwrap (remove the element tag but retain its child elements) during paste when __cleanPastedHTML__ is `true` or when calling `cleanPaste(text)` or `pasteHTML(html,options)` helper methods.
 
+***
 ### Disabling Paste Handling
 
 To disable MediumEditor manipulating pasted content, set the both the `forcePlainText` and `cleanPastedHTML` options to `false`:

README.md

@@ -337,7 +337,8 @@ var editor = new MediumEditor('.editable', {
         cleanPastedHTML: false,
         cleanReplacements: [],
         cleanAttrs: ['class', 'style', 'dir'],
-        cleanTags: ['meta']
+        cleanTags: ['meta'],
+        unwrapTags: []
     }
 });
 ```
@@ -456,7 +457,8 @@ var editor = new MediumEditor('.editable', {
     paste: {
         cleanPastedHTML: true,
         cleanAttrs: ['style', 'dir'],
-        cleanTags: ['label', 'meta']
+        cleanTags: ['label', 'meta'],
+        unwrapTags: ['sub', 'sup']
     },
     anchorPreview: {
         hideDelay: 300