Add galaxy.yml to support install from git

For installing collection from git like:
"ansible-galaxy collection install git+https://..." the galaxy.yml
file is required to be in the collection.
Add galaxy.yml with next version and "-dev".
Fix links for docs and issues.

Change-Id: I74863977732ebea9cd63ccdd2e830a6671a9e955

galaxy.yml.in

@@ -8,10 +8,10 @@ tags:
   - cloud
   - openstack
 dependencies: {}
-repository: https://opendev.org/openstack/ansible-collections-openstack.git
-documentation: https://docs.openstack.org/ansible-collections-openstack
-homepage: https://opendev.org
-issues: https://review.opendev.org/q/project:openstack/ansible-collections-openstack
+repository: https://opendev.org/openstack/ansible-collections-openstack
+documentation: https://docs.ansible.com/ansible/latest/collections/openstack/cloud/index.html
+homepage: https://opendev.org/openstack/ansible-collections-openstack
+issues: https://storyboard.openstack.org/#!/project/openstack/ansible-collections-openstack
 build_ignore:
   - "*.tar.gz"
   - build_artifact
@@ -27,3 +27,9 @@ build_ignore:
   - .zuul.yaml
   - .pytest_cache
   - importer_result.json
+  - .tox
+  - .env
+  - ansible_collections_openstack.egg-info
+  - contrib
+  - changelogs/.plugin-cache.yaml
+  - changelogs/fragments