Add CodeTriage badge to alamofire/alamofire (Alamofire#2458)

Adds a badge showing the number of people helping this repo on CodeTriage.

[![Open Source Helpers](https://www.codetriage.com/alamofire/alamofire/badges/users.svg)](https://www.codetriage.com/alamofire/alamofire)

## What is CodeTriage?

CodeTriage is an Open Source app that is designed to make contributing to Open Source projects easier. It works by sending subscribers a few open issues in their inbox. If subscribers get busy, there is an algorithm that backs off issue load so they do not get overwhelmed

[Read more about the CodeTriage project](https://www.codetriage.com/what).

## Why am I getting this PR?

Your project was picked by the human, @schneems. They selected it from the projects submitted to https://www.codetriage.com and hand edited the PR. How did your project get added to [CodeTriage](https://www.codetriage.com/what)? Roughly over 1 year ago, [linkrjr](https://github.com/linkrjr) added this project to CodeTriage in order to start contributing. Since then, 30 people have subscribed to help this repo.

## What does adding a badge accomplish?

Adding a badge invites people to help contribute to your project. It also lets developers know that others are invested in the longterm success and maintainability of the project.

You can see an example of a CodeTriage badge on these popular OSS READMEs:

- [![Email clients like GMAIL do not render SVG images](https://www.codetriage.com/rails/rails/badges/users.svg)](https://www.codetriage.com/rails/rails) https://github.com/rails/rails
- [![Email clients like GMAIL do not render SVG images](https://www.codetriage.com/crystal-lang/crystal/badges/users.svg)](https://www.codetriage.com/crystal-lang/crystal) https://github.com/crystal-lang/crystal

## Have a question or comment?

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If you have any questions, you can reply back to this PR and they will be answered by @schneems. If you do not want a badge right now, no worries, close the PR, you will not hear from me again.

Thanks for making your project Open Source! Any feedback is greatly appreciated.

CONTRIBUTING.md

@@ -52,6 +52,10 @@ When reporting issues, please include the following:
 
 This information will help us review and fix your issue faster.
 
+## Triage Issues [![Open Source Helpers](https://www.codetriage.com/alamofire/alamofire/badges/users.svg)](https://www.codetriage.com/alamofire/alamofire)
+
+You can triage issues which may include reproducing bug reports or asking for vital information, such as version numbers or reproduction instructions. If you would like to start triaging issues, one easy way to get started is to [subscribe to alamofire on CodeTriage](https://www.codetriage.com/alamofire/alamofire).
+
 ## Developer's Certificate of Origin 1.1
 
 By making a contribution to this project, I certify that:

README.md

@@ -126,7 +126,7 @@ Run `carthage update` to build the framework and drag the built `Alamofire.frame
 
 ### Swift Package Manager
 
-The [Swift Package Manager](https://swift.org/package-manager/) is a tool for automating the distribution of Swift code and is integrated into the `swift` compiler. It is in early development, but Alamofire does support its use on supported platforms. 
+The [Swift Package Manager](https://swift.org/package-manager/) is a tool for automating the distribution of Swift code and is integrated into the `swift` compiler. It is in early development, but Alamofire does support its use on supported platforms.
 
 Once you have your Swift package set up, adding Alamofire as a dependency is as easy as adding it to the `dependencies` value of your `Package.swift`.