ci: Enable toolstate tracking on Azure

Currently just run it through its paces but don't actually push to
official locations. Instead let's just push to a separate fork (mine) as
well as open issues in a separate fork (mine). Make sure that people
aren't pinged for these issues as well!

This should hopefully ensure that everything is working on Azure and
give us a chance to work through any issues that come up.

src/tools/publish_toolstate.py

@@ -3,6 +3,7 @@
 
 import sys
 import re
+import os
 import json
 import datetime
 import collections
@@ -53,6 +54,14 @@ def read_current_status(current_commit, path):
                 return json.loads(status)
     return {}
 
+def gh_url():
+    return os.environ['TOOLSTATE_ISSUES_API_URL']
+
+def maybe_delink(message):
+    if os.environ.get('TOOLSTATE_SKIP_MENTIONS') is not None:
+        return message.replace("@", "")
+    return message
+
 def issue(
     tool,
     maintainers,
@@ -61,13 +70,12 @@ def issue(
     pr_reviewer,
 ):
     # Open an issue about the toolstate failure.
-    gh_url = 'https://api.github.com/repos/rust-lang/rust/issues'
     assignees = [x.strip() for x in maintainers.split('@') if x != '']
     assignees.append(relevant_pr_user)
     response = urllib2.urlopen(urllib2.Request(
-        gh_url,
+        gh_url(),
         json.dumps({
-            'body': textwrap.dedent('''\
+            'body': maybe_delink(textwrap.dedent('''\
             Hello, this is your friendly neighborhood mergebot.
             After merging PR {}, I observed that the tool {} no longer builds.
             A follow-up PR to the repository {} is needed to fix the fallout.
@@ -77,7 +85,7 @@ def issue(
 
             cc @{}, the PR reviewer, and @rust-lang/compiler -- nominating for prioritization.
 
-            ''').format(relevant_pr_number, tool, REPOS.get(tool), relevant_pr_user, pr_reviewer),
+            ''').format(relevant_pr_number, tool, REPOS.get(tool), relevant_pr_user, pr_reviewer)),
             'title': '`{}` no longer builds after {}'.format(tool, relevant_pr_number),
             'assignees': assignees,
             'labels': ['T-compiler', 'I-nominated'],
@@ -216,11 +224,10 @@ if __name__ == '__main__':
         f.write(message)
 
     # Write the toolstate comment on the PR as well.
-    gh_url = 'https://api.github.com/repos/rust-lang/rust/issues/{}/comments' \
-        .format(number)
+    issue_url = gh_url() + '/{}/comments'.format(number)
     response = urllib2.urlopen(urllib2.Request(
-        gh_url,
-        json.dumps({'body': message}),
+        issue_url,
+        json.dumps({'body': maybe_delink(message)}),
         {
             'Authorization': 'token ' + github_token,
             'Content-Type': 'application/json',