Add GitHub issue templates

Airship is migrating from Jira to GitHub issues. This change adds GitHub
issues templates [0] for bug reports and feature requests.

[0] https://help.github.com/en/github/building-a-strong-community/configuring-issue-templates-for-your-repository

Change-Id: I696ad7befdd6f5d8f584f0ea14dbfe7182ad6d12
Signed-off-by: Drew Walters <andrew.walters@att.com>

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,25 @@
+---
+name: Bug report
+about: Report a bug or unexpected airshipctl behavior
+title: ''
+labels: bug
+assignees: ''
+
+---
+
+**Describe the bug**
+A clear and concise description of what the bug is.
+
+**Steps To Reproduce**
+Minimal steps to reproduce the issue.
+
+**Expected behavior**
+A clear and concise description of what you expected to happen.
+
+**Environment**
+- airshipctl Version:
+- Operating System:
+- Kernel version:
+- Kubernetes Version:
+- Go version:
+- Hardware specs (e.g. 4 vCPUs, 16GB RAM, bare metal vs VM):

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,18 @@
+---
+name: Feature request
+about: Suggest an airshipctl feature
+title: ''
+labels: enhancement
+assignees: ''
+
+---
+
+**Problem description (if applicable)**
+A description of the problem or background information that illustrates the need
+for a new feature.
+
+**Proposed change**
+A detailed description of the new, requested behavior.
+
+**Potential impacts**
+Potential security or performance related impacts.