Readme unclear about installation steps

[jorrit-g]

The readme is not entirely clear on how to install the package on iOS.

Creating a Podfile and running Pod install should be sufficient? Later on in the Readme is a part about 'link react-native-linkedin-sdk' which is not necessary if we have done Pod install already?

[joonhocho]

@jorrit-g Pod install is for installing LinkedinSwift which is dependency of this project, doing manual work is for linking to native. So, both are required.