Right to left text fixes.

Fixes #288 

Placeholder and text in both ```WPEditorFields``` can be configured to work RTL or LTR:

![scaled screen shot 2014-10-15 at 5 13 35 pm](https://cloud.githubusercontent.com/assets/154014/4654684/a9cad95e-54b9-11e4-9e66-40acd8671ea1.png)
![scaled screen shot 2014-10-15 at 5 14 45 pm](https://cloud.githubusercontent.com/assets/154014/4654685/abac5ae0-54b9-11e4-86bd-00aa33f70b62.png)

I don't know Arabic so I cannot say if it is really fixed based on their RTL conventions, but I think we are there.

Also, sorry about the mess with Cocoapods...I ran ```pod install``` and it looks like the demo project was updated accordingly.

/cc @diegoreymendez