[docs][glossary] Add page that lists all standardized k8s terms (#5657)

* Add comprehensive glossary page

Additional Authors:
* Andrew Chen <chenopis@users.noreply.github.com>
* Steve Perry <steveperry-53@users.noreply.github.com>

* incorporate Tim's feedback

* address zach's comments

* address more comments

* add additional crosslinking

* Add platform developer, tweak formatting for disambiguation cases or multiparagraph definitions.

_data/glossary/pod.yaml

@@ -0,0 +1,16 @@
+id: pod
+name: Pod
+related:
+- container
+- sidecar
+- deployment
+- statefulset
+tags:
+- core-object
+- fundamental
+short-description: |
+  The smallest and simplest Kubernetes object. A Pod represents a set of running [containers](#term-container) on your cluster.
+long-description: >
+  A Pod is typically set up to run a single primary container.
+  It can also run optional sidecar containers that add supplementary features like logging.
+  Pods are commonly managed by a [Deployment](#term-deployment).