Adds createIndex flag and updates to templateBuilder.js

#### Updates to `doc.jade` template

- Adds check for `input` in cases where `#input-private` is not present in the dom
- Adds classes `sidebar` and `nav` to navigation container in order to target it's anchor tags in css
- Updates mixin name from `otherClasses` to `sidebarNav` to better reflect it's purpose
- Removes trailing whitespace

#### Updates to `templateBuilder.js`

- Adds conditional statement to only run the `index.html` page creation if the `createIndex` flag is true
- Generate an `index.html` starter page if an `/index.js` page does not exist
- Removes trailing slash from `data.pathPrefix` to fix `.//` issue in generated paths

#### Updates to `famous_styles.css`

- Adds `10px` indentation for anchor tags in the sidebar nav

#### Updates to `README.markdown`

- Adds `createIndex` flag docs to README.markdown
- Adds newline at end of file for README.markdown so that it's inline with the editorconfig settings

#### Updates to `cmd.js`

- Adds `createIndex` flag to `cmd.js`

#### Updates to `test-templateBuilder-yuiRunner-yuiSanitizer.js`

- Adds test for `createIndex` flag