message: Added more Slide docs
diff: @@ -36,6 +36,7 @@ Quickly and easily create PowerPoint presentations with a few simple JavaScript
  - [Applying Master Slides / Branding](#applying-master-slides--branding)
  - [Adding Slide Numbers](#adding-slide-numbers)
  - [Slide Number Options](#slide-number-options)
  + - [Slide Return Value](#slide-return-value)
  - [Saving a Presentation](#saving-a-presentation)
  - [Client Browser](#client-browser)
  - [Node.js](#nodejs-1)
  @@ -184,7 +185,7 @@ var slide = pptx.addNewSlide();
  ### Slide Formatting
  ```javascript
  slide.bkgd = 'F1F1F1';
  -slide.color = '696969'
  +slide.color = '696969';
  ```
  ### Slide Formatting Options
  @@ -213,6 +214,17 @@ slide.slideNumber({ x:1.0, y:'90%' });
  | `x` | number | inches | `0.3` | horizontal location | 0-n OR 'n%'. (Ex: `{x:'10%'}` places number 10% from left edge) |
  | `y` | number | inches | `90%` | vertical location | 0-n OR 'n%'. (Ex: `{y:'90%'}` places number 90% down the Slide) |
  +### Slide Return Value
  +The Slide object returns a reference to itself, so calls can be chained.
  +
  +Example:
  +```javascript
  +slide
  +.addImage({ path:'images/logo1.png', x:1, y:2, w:3, h:3 })
  +.addImage({ path:'images/logo2.jpg', x:5, y:3, w:3, h:3 })
  +.addImage({ path:'images/logo3.png', x:9, y:4, w:3, h:3 });
  +```
  +
  **************************************************************************************************
  ## Saving a Presentation
  @@ -244,6 +256,12 @@ pptx.save( 'Node_Demo', saveCallback );
  **************************************************************************************************
  # Presentations: Adding Objects
  +Objects on the Slide are ordered from back-to-front based upon the order they were added.
  +
  +For example, if you add an Image, then a Shape, then a Textbox: the Textbox will be in front of the Shape,
  +which is in front of the Image.
  +
  +
  **************************************************************************************************
  ## Adding Text
  ```javascript
  @@ -255,7 +273,7 @@ slide.addText([ {text:'TEXT', options:{OPTIONS}} ]);
  ### Text Options
  | Option | Type | Unit | Default | Description | Possible Values |
  -| :----------- | :------ | :----- | :-------- | :------------------ | :--------------- |
  +| :----------- | :------ | :------ | :-------- | :------------------ | :--------------- |
  | `x` | number | inches | `1.0` | horizontal location | 0-n OR 'n%'. (Ex: `{x:'50%'}` will place object in the middle of the Slide) |
  | `y` | number | inches | `1.0` | vertical location | 0-n OR 'n%'. |
  | `w` | number | inches | | width | 0-n OR 'n%'. (Ex: `{w:'50%'}` will make object 50% width of the Slide) |
  @@ -280,7 +298,7 @@ slide.addText([ {text:'TEXT', options:{OPTIONS}} ]);
  ### Text Shadow Options
  | Option | Type | Unit | Default | Description | Possible Values |
  -| :----------- | :------ | :------ | :-------- | :--------------------- | :--------------- |
  +| :----------- | :------ | :------ | :-------- | :------------------ | :--------------------------------------- |
  | `type` | string | | outer | shadow type | `outer` or `inner` |
  | `angle` | number | degrees | | shadow angle | 0-359. Ex: `{ angle:180 }` |
  | `blur` | number | points | | blur size | 1-256. Ex: `{ blur:3 }` |
  