resubmit previous PR into restructure branch
initial revision of Using an Entity as per recommendations of @raisinbread.

* Removal of in-page menu.
* Moved custom finders back to adding-functions... (left a hyperlink)
* Made the description of parameters more conversational
* Removed headers text of method names

Notes changed to blockquotes.  Recommend the following addition in li3_docs CSS (will submit as a separate PR in li3_docs if all are agreeable)..

```CSS
.markdown blockquote {
    font-size: 1em;
    background-color: #efefef;
}
```
* Removal of in-page menu.
* Other clean ups and restructuring to make it more conversational and less like the API guide.
update the saving data title to saving entities
Merge pull request #45 from AndrewPodner/restructure-models

resubmit previous PR into restructure branch