Add a separate issue form to report crashes (python#9549)

.github/ISSUE_TEMPLATE/crash.md

@@ -0,0 +1,41 @@
+---
+name: Crash Report
+about: Crash (traceback or "INTERNAL ERROR")
+labels: "crash"
+---
+
+<!--
+  Use this form only if mypy reports an "INTERNAL ERROR" and/or gives a traceback.
+  Please include the traceback and all other messages below (use `mypy --show-traceback`).
+-->
+
+**Crash Report**
+
+(Tell us what happened.)
+
+**Traceback**
+
+```
+(Insert traceback and other messages from mypy here -- use `--show-traceback`.)
+```
+
+**To Reproduce**
+
+(Write what you did to reproduce the crash.  Full source code is
+appreciated.  We also very much appreciate it if you try to narrow the
+source down to a small stand-alone example.)
+
+**Your Environment**
+
+<!-- Include as many relevant details about the environment you experienced the bug in -->
+
+- Mypy version used:
+- Mypy command-line flags:
+- Mypy configuration options from `mypy.ini` (and other config files):
+- Python version used:
+- Operating system and version:
+
+<!--
+You can freely edit this text, please remove all the lines
+you believe are unnecessary.
+-->