Issue/PR templates (#180)

* create .github directory to hold issue/PR templates and contributing guide

* update link to Contributing guide in Readme
diff --git a/.github/PULL_REQUEST_TEMPLATE b/.github/PULL_REQUEST_TEMPLATE
new file mode 100644
index 0000000..43aafa0
--- /dev/null
+++ b/.github/PULL_REQUEST_TEMPLATE
@@ -0,0 +1,9 @@
+Prior to a PR being reviewed, there needs to be a Github issue that the PR
+addresses. Replace the brackets and text below with that issue number.
+
+For #[PUT ISSUE NUMBER HERE]
+
+Links to the line numbers/files in the OpenStack source code that support the
+code in this PR:
+
+[PUT URLS HERE]