Appveyor CI: sort environmental variables

To avoid future duplicates.

scripts/test/appveyor-irc-notify.py

@@ -51,19 +51,19 @@ delineate multiple messages.
 
 
 Example:
-export APPVEYOR_URL=https://ci.appveyor.com
+export APPVEYOR_ACCOUNT_NAME=isislovecruft
+export APPVEYOR_BUILD_VERSION=1
 export APPVEYOR_PROJECT_NAME=tor
-export APPVEYOR_REPO_COMMIT_AUTHOR=isislovecruft
-export APPVEYOR_REPO_COMMIT_TIMESTAMP=2018-04-23
-export APPVEYOR_REPO_PROVIDER=github
-export APPVEYOR_REPO_BRANCH=repo_branch
+export APPVEYOR_PULL_REQUEST_NUMBER=pull_request_number
 export APPVEYOR_PULL_REQUEST_TITLE=pull_request_title
-export APPVEYOR_BUILD_VERSION=1
+export APPVEYOR_REPO_BRANCH=repo_branch
 export APPVEYOR_REPO_COMMIT=22c95b72e29248dc4de9b85e590ee18f6f587de8
+export APPVEYOR_REPO_COMMIT_AUTHOR=isislovecruft
 export APPVEYOR_REPO_COMMIT_MESSAGE="some IRC test"
-export APPVEYOR_ACCOUNT_NAME=isislovecruft
-export APPVEYOR_PULL_REQUEST_NUMBER=pull_request_number
+export APPVEYOR_REPO_COMMIT_TIMESTAMP=2018-04-23
 export APPVEYOR_REPO_NAME=isislovecruft/tor
+export APPVEYOR_REPO_PROVIDER=github
+export APPVEYOR_URL=https://ci.appveyor.com
 python ./appveyor-irc-notify.py irc.oftc.net:6697 tor-ci '{repo_name} {repo_branch} {short_commit} - {repo_commit_author}: {repo_commit_message}','Build #{build_version} passed. Details: {build_url} |  Commit: {commit_url}
 
 See also https://github.com/gridsync/gridsync/blob/master/appveyor.yml for examples
@@ -96,25 +96,25 @@ def appveyor_vars():
                 v.replace('APPVEYOR_', '').lower(),
                 os.getenv(v, '').decode('utf-8')
             ) for v in [
-                'APPVEYOR_URL',
-                'APPVEYOR_REPO_COMMIT_MESSAGE_EXTENDED',
-                'APPVEYOR_REPO_BRANCH',
-                'APPVEYOR_REPO_COMMIT_AUTHOR',
-                'APPVEYOR_REPO_COMMIT_AUTHOR_EMAIL',
-                'APPVEYOR_REPO_COMMIT_TIMESTAMP',
-                'APPVEYOR_REPO_PROVIDER',
+                'APPVEYOR_ACCOUNT_NAME',
+                'APPVEYOR_BUILD_VERSION',
                 'APPVEYOR_PROJECT_NAME',
-                'APPVEYOR_PULL_REQUEST_HEAD_REPO_NAME',
-                'APPVEYOR_PULL_REQUEST_HEAD_REPO_BRANCH',
                 'APPVEYOR_PULL_REQUEST_HEAD_COMMIT',
+                'APPVEYOR_PULL_REQUEST_HEAD_REPO_BRANCH',
+                'APPVEYOR_PULL_REQUEST_HEAD_REPO_NAME',
+                'APPVEYOR_PULL_REQUEST_NUMBER',
                 'APPVEYOR_PULL_REQUEST_TITLE',
-                'APPVEYOR_BUILD_VERSION',
+                'APPVEYOR_REPO_BRANCH',
                 'APPVEYOR_REPO_COMMIT',
+                'APPVEYOR_REPO_COMMIT_AUTHOR',
+                'APPVEYOR_REPO_COMMIT_AUTHOR_EMAIL',
                 'APPVEYOR_REPO_COMMIT_MESSAGE',
-                'APPVEYOR_ACCOUNT_NAME',
-                'APPVEYOR_PULL_REQUEST_NUMBER',
+                'APPVEYOR_REPO_COMMIT_MESSAGE_EXTENDED',
+                'APPVEYOR_REPO_COMMIT_TIMESTAMP',
                 'APPVEYOR_REPO_NAME',
+                'APPVEYOR_REPO_PROVIDER',
                 'APPVEYOR_REPO_TAG_NAME',
+                'APPVEYOR_URL',
             ]
     ])