update branch to main (elastic#36)

Author: v1v

CONTRIBUTING.md

@@ -70,7 +70,7 @@ Once your changes are ready to submit for review:
 4. Rebase your changes
 
     Update your local repository with the most recent code from the main repo,
-    and rebase your branch on top of the latest master branch.
+    and rebase your branch on top of the latest main branch.
     We prefer your initial changes to be squashed into a single commit.
     Later,
     if we ask you to make changes,
@@ -105,7 +105,7 @@ composer test
 
 ### Workflow
 
-All feature development and most bug fixes hit the master branch first.
+All feature development and most bug fixes hit the main branch first.
 Pull requests should be reviewed by someone with commit access.
 Once approved, the author of the pull request,
 or reviewer if the author does not have commit access,
@@ -114,7 +114,7 @@ should "Squash and merge".
 ### Design considerations
 
 #### Compatibility
-    
+
 Coming soon [TBD]
 
 ### Coding guidelines
@@ -123,4 +123,4 @@ Coming soon [TBD]
 
 ### Releasing
 
-See [RELEASE.md](RELEASE.md) for details on releasing.
+See [RELEASE.md](RELEASE.md) for details on releasing.

README.md

@@ -1,4 +1,4 @@
-[![Build Status](https://apm-ci.elastic.co/buildStatus/icon?job=apm-agent-php%2Fecs-logging-php-mbp%2Fmaster)](https://apm-ci.elastic.co/job/apm-agent-php/job/ecs-logging-php-mbp/job/master/)
+[![Build Status](https://apm-ci.elastic.co/buildStatus/icon?job=apm-agent-php%2Fecs-logging-php-mbp%2Fmain)](https://apm-ci.elastic.co/job/apm-agent-php/job/ecs-logging-php-mbp/job/main/)
 
 # ECS Logging for PHP
 
@@ -16,7 +16,7 @@ composer require elastic/ecs-logging
 ```
 
 ## Examples and Usage
-* [Monolog v2.0](https://github.com/elastic/ecs-logging-php/blob/master/docs/Monolog_v2.md)
+* [Monolog v2.0](https://github.com/elastic/ecs-logging-php/blob/main/docs/Monolog_v2.md)
 
 ## Library Support
 * Currently only [Monolog:2.*](https://github.com/Seldaek/monolog) is supported.
@@ -32,4 +32,4 @@ composer require elastic/ecs-logging
 See [contributing documentation](CONTRIBUTING.md).
 
 ## License
-This software is licensed under the [Apache 2 license](https://github.com/elastic/ecs-logging-php/blob/master/LICENSE).
+This software is licensed under the [Apache 2 license](https://github.com/elastic/ecs-logging-php/blob/main/LICENSE).

RELEASE.md

@@ -2,7 +2,7 @@
 
 ## CI based
 
-The release process is also automated in the way any specific commit, from the master branch ideally, can be potentially released, for such it's required the below steps:
+The release process is also automated in the way any specific commit, from the main branch ideally, can be potentially released, for such it's required the below steps:
 
 1. Checkout the commit to be released
 1. Create a tag with the format `[0-9]+.[0-9]+.[0-9]+`, i.e.: `1.0.2`

docs/Monolog_v2.md

@@ -30,7 +30,7 @@ catch(\Exception $exception) {
     // log and do other things ..
 }
 ```
-ECS [docs](https://www.elastic.co/guide/en/ecs/current/ecs-error.html) | Service [class](https://github.com/elastic/ecs-logging-php/blob/master/src/Elastic/Types/Error.php)
+ECS [docs](https://www.elastic.co/guide/en/ecs/current/ecs-error.html) | Service [class](https://github.com/elastic/ecs-logging-php/blob/main/src/Elastic/Types/Error.php)
 
 ### Service
 The service context enables you to provide more attributes describing your service. Setting a version can help you track system behaviour over time.
@@ -43,7 +43,7 @@ $serviceContext->setVersion('1.2.42');
 
 $logger->notice('this message adds service context, nice :)', ['service' => $serviceContext]);
 ```
-ECS [docs](https://www.elastic.co/guide/en/ecs/current/ecs-service.html) | Service [class](https://github.com/elastic/ecs-logging-php/blob/master/src/Elastic/Types/Service.php)
+ECS [docs](https://www.elastic.co/guide/en/ecs/current/ecs-service.html) | Service [class](https://github.com/elastic/ecs-logging-php/blob/main/src/Elastic/Types/Service.php)
 
 ### User
 The user context allows you to enrich your log entries with user specific attributes such as `user.id` or `user.name` to simplify the discovery of specific log events.
@@ -56,7 +56,7 @@ $userContext->setEmail('hello@example.com');
 
 $logger->notice('heya, the context helps you to trace logs more effective', ['user' => $userContext]);
 ```
-ECS [docs](https://www.elastic.co/guide/en/ecs/current/ecs-user.html) | Service [class](https://github.com/elastic/ecs-logging-php/blob/master/src/Elastic/Types/User.php)
+ECS [docs](https://www.elastic.co/guide/en/ecs/current/ecs-user.html) | Service [class](https://github.com/elastic/ecs-logging-php/blob/main/src/Elastic/Types/User.php)
 
 Please be aware that a method `User::setHash` is available, if you want to obfuscate `user.id`, `user.name`, etc.
 
@@ -69,4 +69,4 @@ $tracingContext = new Tracing('<trace-id>', '<transaction-id>');
 
 $logger->notice('I am a log message with a trace id, so you can do awesome things in the Logs UI', ['tracing' => $tracingContext]);
 ```
-ECS [docs](https://www.elastic.co/guide/en/ecs/current/ecs-tracing.html) | Tracing [class](https://github.com/elastic/ecs-logging-php/blob/master/src/Elastic/Types/Tracing.php)
+ECS [docs](https://www.elastic.co/guide/en/ecs/current/ecs-tracing.html) | Tracing [class](https://github.com/elastic/ecs-logging-php/blob/main/src/Elastic/Types/Tracing.php)