Create a Github issue template

So that we can stop asking common questions like "What version of Open
MPI are you using?", etc.

[skip ci]
bot:notest

Signed-off-by: Jeff Squyres <jsquyres@cisco.com>

.github/issue_template.md

@@ -0,0 +1,29 @@
+Thank you for taking the time to submit an issue!
+
+## Background information
+
+### What version of Open MPI are you using? (e.g., v1.10.3, v2.1.0, git branch name and hash, etc.)
+
+
+
+### Describe how Open MPI was installed (e.g., from a source/distribution tarball, from a git clone, from an operating system distribution package, etc.)
+
+
+
+### Please describe the system on which you are running
+
+* Operating system/version: 
+* Computer hardware: 
+* Network type: 
+
+-----------------------------
+
+## Details of the problem
+
+Please describe, in detail, the problem that you are having, including the behavior you expect to see, the actual behavior that you are seeing, steps to reproduce the problem, etc.  It is most helpful if you can attach a small program that a developer can use to reproduce your problem.
+
+**Note**: If you include verbatim output (or a code block), please use a [GitHub Markdown](https://help.github.com/articles/creating-and-highlighting-code-blocks/) code block like below:
+```shell
+shell$ mpirun -np 2 ./hello_world
+```
+