Rename main branch and references to it.

Author: MarcCote

.azure/pipelines/coverage.yml

@@ -4,7 +4,7 @@
 # https://docs.microsoft.com/azure/devops/pipelines/languages/python
 
 trigger:
-- master
+- main
 
 pool:
   vmImage: 'ubuntu-latest'

.azure/pipelines/prerelease.yml

@@ -1,4 +1,4 @@
-# Release code in the master branch to PyPi
+# Release code in the main branch to PyPi
 
 stages:
 - stage: Prerelease_on_PyPi

.azure/pipelines/release.yml

@@ -1,4 +1,4 @@
-# Release code in the master branch to PyPi
+# Release code in the main branch to PyPi
 
 jobs:
 - job:

.azure/pipelines/security.yml

@@ -1,7 +1,7 @@
 # Run the Component Governance Detection task
 
 trigger:
-- master
+- main
 
 pool:
   vmImage: 'ubuntu-latest'

.azure/pipelines/tests.yml

@@ -1,5 +1,5 @@
 trigger:
-- master
+- main
 
 stages:
 - stage: Test

README.md

@@ -1,6 +1,6 @@
 # TextWorld
 
-[![Build Status](https://dev.azure.com/maluuba/TextWorld/_apis/build/status/microsoft.TextWorld?branchName=master)](https://dev.azure.com/maluuba/TextWorld/_build/latest?definitionId=180&branchName=master) [![PyPI version](https://badge.fury.io/py/textworld.svg)](https://badge.fury.io/py/textworld) [![Documentation Status](https://readthedocs.org/projects/textworld/badge/?version=latest)](https://textworld.readthedocs.io/en/stable/?badge=stable) [![Join the chat at https://gitter.im/Microsoft/TextWorld](https://badges.gitter.im/Microsoft/TextWorld.svg)](https://gitter.im/Microsoft/TextWorld?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
+[![Build Status](https://dev.azure.com/maluuba/TextWorld/_apis/build/status/microsoft.TextWorld?branchName=main)](https://dev.azure.com/maluuba/TextWorld/_build/latest?definitionId=180&branchName=main) [![PyPI version](https://badge.fury.io/py/textworld.svg)](https://badge.fury.io/py/textworld) [![Documentation Status](https://readthedocs.org/projects/textworld/badge/?version=latest)](https://textworld.readthedocs.io/en/stable/?badge=stable) [![Join the chat at https://gitter.im/Microsoft/TextWorld](https://badges.gitter.im/Microsoft/TextWorld.svg)](https://gitter.im/Microsoft/TextWorld?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
 
 A text-based game generator and extensible sandbox learning environment for training and testing reinforcement learning (RL) agents. Also check out [aka.ms/textworld](https://aka.ms/textworld/) for more info about TextWorld and its creators. Have questions or feedback about TextWorld? Send them to textworld@microsoft.com or use the Gitter channel listed above.
 

textworld/challenges/tw_cooking/README.md

@@ -6,7 +6,7 @@
 
 The development branch of TextWorld can be installed using
 
-    pip install https://github.com/Microsoft/TextWorld/archive/master.zip
+    pip install https://github.com/Microsoft/TextWorld/archive/main.zip
 
 ## Usage
 

textworld/generator/game.py

@@ -1037,12 +1037,12 @@ def winning_policy(self) -> Optional[List[Action]]:
             # Some quests don't have triggering policy.
             return None
 
-        master_quest_tree = ActionDependencyTree(kb=self.game.kb,
-                                                 element_type=ActionDependencyTreeElement,
-                                                 trees=trees)
+        main_quest_tree = ActionDependencyTree(kb=self.game.kb,
+                                               element_type=ActionDependencyTreeElement,
+                                               trees=trees)
 
         # Discard all "trigger" actions.
-        return tuple(a for a in master_quest_tree.flatten() if a.name != "trigger")
+        return tuple(a for a in main_quest_tree.flatten() if a.name != "trigger")
 
     def update(self, action: Action) -> None:
         """ Update the state of the game given the provided action.