Merge #1

1: Initial CI support. r=ltratt a=vext01

This is preliminary CI support for CPython.

A test is failing:
```
test test_signal failed -- Traceback (most recent call last):
  File "/ci/Lib/test/test_signal.py", line 184, in test_main
    self.fail(tb)
AssertionError: Traceback (most recent call last):
  File "/ci/Lib/test/test_signal.py", line 167, in test_main
    self.run_test()
  File "/ci/Lib/test/test_signal.py", line 94, in run_test
    child = ignoring_eintr(subprocess.Popen, ['kill', '-HUP', str(pid)])
  File "/ci/Lib/test/test_signal.py", line 32, in ignoring_eintr
    return __func(*args, **kwargs)
  File "/ci/Lib/subprocess.py", line 394, in __init__
    errread, errwrite)
  File "/ci/Lib/subprocess.py", line 1047, in _execute_child
    raise child_exception
OSError: [Errno 2] No such file or directory
```

Does anyone know anything about it? Could have cloned at a bad time?

Co-authored-by: Edd Barrett <[email protected]>

Author: bors[bot]

.buildbot.sh

@@ -0,0 +1,7 @@
+#!/bin/sh
+
+set -e
+
+./configure --enable-optimizations
+make -j `nproc`
+./python -m test

bors.toml

@@ -0,0 +1,10 @@
+# The service providing the commit statuses to GitHub.
+status = [
+  "buildbot/buildbot-build-script"
+]
+
+# Allow 30 minutes for builds.
+timeout_sec = 1350
+
+# Have bors delete auto-merged branches (if possible).
+delete_merged_branches = true