chore: update GitHub branch references to use HEAD (#108)

Author: thinkingserious

CONTRIBUTING.md

@@ -50,7 +50,7 @@ We welcome direct contributions to the smtpapi-java code base. Thank you!
 ##### Prerequisites #####
 
 - Java version Oracle JDK 7, 8 or OpenJDK 7
-- See [build.gradle](https://github.com/sendgrid/smtpapi-java/blob/master/build.gradle) for dependencies.
+- See [pom.xml](pom.xml) for dependencies.
 
 ##### Initial setup: #####
 
@@ -62,7 +62,7 @@ cd smtpapi-java
 
 ##### Execute: #####
 
-See the [examples folder](https://github.com/sendgrid/smtpapi-java/tree/master/examples) to get started quickly.
+See the [examples folder](examples) to get started quickly.
 
 ```bash
 cd examples
@@ -89,9 +89,9 @@ Source code.
 
 All PRs require passing tests before the PR will be reviewed.
 
-All test files are in the [`/src/test/java/com/sendgrid/smtpapi/`](https://github.com/sendgrid/smtpapi-java/tree/master/src/test/java/com/sendgrid/smtpapi/) directory.
+All test files are in the [`/src/test/java/com/sendgrid/smtpapi/`](src/test/java/com/sendgrid/smtpapi/) directory.
 
-For the purposes of contributing to this repo, please update the [`SMTPAPITest.java`](https://github.com/sendgrid/smtpapi-java/blob/master/src/test/java/com/sendgrid/smtpapi/SMTPAPITest.java) file with unit tests as you modify the code.
+For the purposes of contributing to this repo, please update the [`SMTPAPITest.java`](src/test/java/com/sendgrid/smtpapi/SMTPAPITest.java) file with unit tests as you modify the code.
 
 To run the tests:
 
@@ -150,7 +150,7 @@ Please run your code through:
 5. Locally merge (or rebase) the upstream development branch into your topic branch:
 
    ```bash
-   git pull [--rebase] upstream master
+   git pull [--rebase] upstream main
    ```
 
 6. Push your topic branch up to your fork:
@@ -160,7 +160,7 @@ Please run your code through:
    ```
 
 7. [Open a Pull Request](https://help.github.com/articles/using-pull-requests/)
-    with a clear title and description against the `master` branch. All tests must be passing before we will review the PR.
+    with a clear title and description against the `main` branch. All tests must be passing before we will review the PR.
 
 <a name="code-reviews"></a>
 ## Code Reviews

README.md

@@ -1,6 +1,6 @@
-![SendGrid Logo](https://uiux.s3.amazonaws.com/2016-logos/email-logo%402x.png)
+![SendGrid Logo](twilio_sendgrid_logo.png)
 
-[![BuildStatus](https://travis-ci.org/sendgrid/smtpapi-java.svg?branch=master)](https://travis-ci.org/sendgrid/smtpapi-java)
+[![BuildStatus](https://travis-ci.org/sendgrid/smtpapi-java.svg?branch=main)](https://travis-ci.org/sendgrid/smtpapi-java)
 [![Email Notifications Badge](https://dx.sendgrid.com/badge/java)](https://dx.sendgrid.com/newsletter/java)
 [![Twitter Follow](https://img.shields.io/twitter/follow/sendgrid.svg?style=social&label=Follow)](https://twitter.com/sendgrid)
 [![GitHub contributors](https://img.shields.io/github/contributors/sendgrid/smtpapi-java.svg)](https://github.com/sendgrid/smtpapi-java/graphs/contributors)
@@ -11,7 +11,7 @@
 # Announcements
 **The default branch name for this repository has been changed to `main` as of 07/27/2020.**
 
-All updates to this module is documented in our [CHANGELOG](https://github.com/sendgrid/smtpapi-java/blob/master/CHANGELOG.md).
+All updates to this module is documented in our [CHANGELOG](CHANGELOG.md).
 
 # Table of Contents
 - [Installation](#installation)
@@ -74,7 +74,7 @@ source ./sendgrid.env
 
 ## Dependencies
 
-- See [build.gradle](https://github.com/sendgrid/smtpapi-java/blob/master/build.gradle#L47).
+- See [pom.xml](pom.xml).
 
 <a name="quick-start"></a>
 # Quick Start
@@ -96,7 +96,7 @@ public class Example {
 # Usage
 
 - [SendGrid Docs](https://sendgrid.com/docs/API_Reference/SMTP_API/index.html)
-- [Example Code](https://github.com/sendgrid/smtpapi-java/tree/master/examples)
+- [Example Code](examples)
 
 <a name="roadmap"></a>
 # Roadmap
@@ -106,14 +106,14 @@ If you are interested in the future direction of this project, please take a loo
 <a name="contribute"></a>
 # How to Contribute
 
-We encourage contribution to our projects, please see our [CONTRIBUTING](https://github.com/sendgrid/smtpapi-java/blob/master/CONTRIBUTING.md) guide for details.
+We encourage contribution to our projects, please see our [CONTRIBUTING](CONTRIBUTING.md) guide for details.
 
 Quick links:
 
-- [Feature Request](https://github.com/sendgrid/smtpapi-java/blob/master/CONTRIBUTING.md#feature-request)
-- [Bug Reports](https://github.com/sendgrid/smtpapi-java/blob/master/CONTRIBUTING.md#submit-a-bug-report)
-- [Improvements to the Codebase](https://github.com/sendgrid/smtpapi-java/blob/master/CONTRIBUTING.md#improvements_to_the_codebase)
-- [Review Pull Requests](https://github.com/sendgrid/smtpapi-java/blob/master/CONTRIBUTING.md#code-reviews)
+- [Feature Request](CONTRIBUTING.md#feature-request)
+- [Bug Reports](CONTRIBUTING.md#submit-a-bug-report)
+- [Improvements to the Codebase](CONTRIBUTING.md#improvements_to_the_codebase)
+- [Review Pull Requests](CONTRIBUTING.md#code-reviews)
 
 <a name="about"></a>
 # About

pom.xml

@@ -16,7 +16,7 @@
   <licenses>
     <license>
       <name>The MIT License (MIT)</name>
-      <url>https://github.com/sendgrid/smtpapi-java/blob/master/LICENSE</url>
+      <url>https://github.com/sendgrid/smtpapi-java/blob/HEAD/LICENSE</url>
       <distribution>repo</distribution>
     </license>
   </licenses>