Update docs and readme

Author: bbrala

README.md

@@ -106,6 +106,7 @@ Font-Awesome icons used from [encharm/Font-Awesome-SVG-PNG](https://github.com/e
 ### Unreleased ###
 
 * Fixed a swith to use the correct type for separators (thanks @RareDevil)
+* Added support for providing a function as zIndex value in options object (thanks @eivindga)
 
 ###  2.0.1 (December 3rd 2015) ###
 

documentation/docs.md

@@ -184,16 +184,22 @@ $.contextMenu({
 
 ### zIndex
 
-Specifies the offset to add to the calculated zIndex of the [trigger](#trigger) element. Set to `0` to prevent zIndex manipulation
+Specifies the offset to add to the calculated zIndex of the [trigger](#trigger) element. Set to `0` to prevent zIndex manipulation. Can be a function that returns an int to calculate the zIndex on build.
 
-`zIndex`: `int` default: `1` 
+`zIndex`: `int`|`function` default: `1` 
 
 #### Example
 ```javascript
 $.contextMenu({
     selector: 'span.context-menu',
     zIndex: 10
 });
+
+$.contextMenu({
+    selector: 'span.context-menu',
+    zIndex: function($trigger, opt){
+        return 120;
+});
 ```
 
 ### className