* Adding new guides
* Replaced backend with engine
* Grammar for the encryption guide
* Grammar and Markdown style for the Transite Rewrap guide
See
https://github.com/hashicorp/engineering-docs/blob/master/writing/markdown.md
for notes on numbered Markdown lists.
* grammar and wording updates for ref arch guide
* Updating replication diagram
* Removing multi-tenant pattern guide
* Added a note 'Enterprise Only'
* Removing multi-tenant pattern guide
* Modified the topic order
* Grammar and Markdown formatting
* Grammar, Markdown syntax, and phrasing
* Grammar and Markdown syntax
* Replaced 'backend' with appropriate terms
* Added a note clarifying that replication is an enterprise-only feature
* Updated the diagram & added additional resource links
* update some grammar and ordering
* Removed the inaccurate text in index for EaaS
