Correct the spelling of CocoaPods in README

[ReadmeCritic]

This pull requests corrects the spelling of CocoaPods 🤓
https://github.com/CocoaPods/shared_resources/tree/master/media

One day I’ll make a bot that looks through the READMEs of all Pods, looks to see if it uses “Cocoapods” and PRs “CocoaPods” :D

— Ørta (@orta) February 10, 2016

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Created with cocoapods-readme.

[codecov-io]

Current coverage is 99.41%

Merging #3 into master will not affect coverage as of 8789266

@@            master      #3   diff @@
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  Files            5       5       
  Stmts          170     170       
  Branches         0       0       
  Methods                          
======================================
  Hit            169     169       
  Partial          0       0       
  Missed           1       1       

Review entire Coverage Diff as of 8789266

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