Published Flipper-PeerTalk dependency on Cocoapods (#395)

Summary:
I have published the new tag of Peertalk on my [fork](https://github.com/priteshrnandgaonkar/peertalk) and published a [Flipper-PeerTalk](80e4cd9a05/Specs/d/6/6/Flipper-PeerTalk/0.0.4/Flipper-PeerTalk.podspec.json) pod on cocoapods. There was no reply on the [request](https://github.com/rsms/peertalk/issues/48) to publish the new version of the peertalk on their repository and it was blocking us to publish Flipper and FlipperKit pods to Cocoapods. For more context follow the issue #132. With this PR we would have all our dependencies on cocoapods and thus we can now publish Flipper and FlipperKit pods on the cocoapods master repository.

I have also added the Flipper-PeerTalk podspec file for future updates.
Pull Request resolved: https://github.com/facebook/flipper/pull/395

Reviewed By: passy

Differential Revision: D14642440

Pulled By: priteshrnandgaonkar

fbshipit-source-id: 7847c19cddea358ffb62d2c6f16fc06d1afa1ea1

iOS/SampleSwift/SampleSwift.xcodeproj/project.pbxproj

@@ -357,7 +357,6 @@
 				OTHER_LDFLAGS = (
 					"$(inherited)",
 					"-ObjC",
-					"-l\"PeerTalk\"",
 					"-l\"crypto\"",
 					"-l\"event\"",
 					"-l\"event_core\"",
@@ -411,7 +410,6 @@
 				OTHER_LDFLAGS = (
 					"$(inherited)",
 					"-ObjC",
-					"-l\"PeerTalk\"",
 					"-l\"crypto\"",
 					"-l\"event\"",
 					"-l\"event_core\"",