Docs site (#269)

* Set up documentation site using jekyll

* Add workflow for deploying docs

* Ini formatting is hard to read

* Add instructions on how to run docs locally

* Work through docs

* Remove content from README

* Miscellaneous fixes

* Fix artifact upload

docs/how-tos/manual-trigger.md

@@ -0,0 +1,20 @@
+---
+title: Trigger a backp manually
+layout: default
+parent: How Tos
+nav_order: 8
+---
+
+# Trigger a backup manually
+
+You can manually trigger a backup run outside of the defined cron schedule by executing the `backup` command inside the container:
+
+```console
+docker exec <container_ref> backup
+```
+
+If the container is configured to run multiple schedules, you can source the respective conf file before invoking the command:
+
+```console
+docker exec <container_ref> /bin/sh -c 'set -a; source /etc/dockervolumebackup/conf.d/myconf.env; set +a && backup'
+```