Garrett McCullough 8117fa16c9 Improve the documentation for ListView and ListViewDataSource ...

Summary:
What existing problem does the pull request solve?
My motivation was to improve the documentation for ListView and ListViewDataSource because I always have trouble remembering how they work and the documentation was lacking an example for `cloneWithRowsAndSections`

My PR does the following:
* add a note about how headers and footers are rendered on a horizontal ListView
* fix a typo in an example
* clarify that the sectionIdentities should match the keys or array indexes of the data source
* add an example of cloneWithRowsAndSections
* add notes on the return values of `getRowCount` and `getRowAndSectionCount`

n/a; documentation only

![screenshot of ListViewDataSource changes](https://cloud.githubusercontent.com/assets/580060/25768881/d339544a-31c1-11e7-88a1-5e60bc008500.png)
Closes https://github.com/facebook/react-native/pull/13811

Differential Revision: D5473192

Pulled By: hramos

fbshipit-source-id: f31fc6edfdeb8dff75d39bbcceda06fd839df934

2017-07-21 14:31:17 -07:00

..

__flowtests__

Enforce Prettier for @format

2017-07-10 15:37:36 -07:00

__tests__

Codemod prettier to 1.5.2

2017-06-28 12:50:30 -07:00

ListView

Improve the documentation for ListView and ListViewDataSource

2017-07-21 14:31:17 -07:00

FillRateHelper.js

Codemod prettier to 1.5.2

2017-06-28 12:50:30 -07:00

FlatList.js

Remove typo

2017-07-18 17:46:33 -07:00

MetroListView.js

Codemod prettier to 1.5.2

2017-06-28 12:50:30 -07:00

SectionList.js

Update sectionList keyExtractor docs

2017-07-14 13:23:21 -07:00

ViewabilityHelper.js

prettier

2017-06-12 22:45:49 -07:00

VirtualizedList.js

Be able to scroll to last item in list

2017-07-13 00:03:51 -07:00

VirtualizedSectionList.js

Codemod prettier to 1.5.2

2017-06-28 12:50:30 -07:00

VirtualizeUtils.js

Codemod prettier to 1.5.2

2017-06-28 12:50:30 -07:00