README: direct users to the examples (#160)

We can come back and add example usage in this main README if that's useful, but for now pointing to the examples that are fleshed out and are known to compile is a pragmatic step forward. It also gives newcomers links to binaries they can run to understand what Tessera can do, before they start writing any code.

README.md

@@ -12,7 +12,7 @@ over the past decade of building and operating transparency logs in production e
 
 Tessera goals:
 
-*   [Tiles-native API](https://github.com/C2SP/C2SP/blob/main/tlog-tiles.md) and storage
+*   [tlog-tiles API][] and storage
 *   Support for both cloud and on-premises infrastructure
     *   GCP and AWS support will be provided initially
     *   Cloud agnostic MySQL and POSIX filesystem support
@@ -27,7 +27,7 @@ Tessera goals:
 *   Broadly similar write-throughput and write-availability, and potentially _far_ higher read-throughput
     and read-availability compared to Trillian v1 (dependent on underlying infrastructure)
 *   Enable building of arbitrary log personalities, including support for the peculiarities of a
-    [Static CT API](https://c2sp.org/static-ct-api) compliant log.
+    [Static CT API][] compliant log.
 
 ### Status
 
@@ -48,17 +48,16 @@ migration to Tessera and adopting the patterns it encourages.
 
 ### Getting started
 
-#### Usage
+Take a look at the example personalities in the `/cmd/` directory:
+  - [example-posix](./cmd/example-posix/): example of operating a log backed by a local filesystem
+    - This example is not a long-lived process; running the command integrates entries into the log which lives only as files
+  - [example-mysql](./cmd/example-mysql/): example of operating a log that uses MySQL
+    - This example is easiest deployed via `docker compose`, which allows for easy setup and teardown
+  - [example-gcp](./cmd/example-gcp/): example of operating a log running in GCP
+    - This example can be deployed via terraform (see the [deployment](./deployment/) directory)
 
-```go
-
-import (
-    tessera "github.com/transparency-dev/trillian-tessera"
-)
-
-// TODO...
-
-```
+The `main.go` files for each of these example personalities try to strike a balance when demonstrating features of Tessera between simplicity, and demonstrating best practices.
+Please raise issues against the repo, or chat to us in [Slack](#contact) if you have ideas for making the examples more accessible!
 
 ### Contributing
 
@@ -77,3 +76,6 @@ This repo is licensed under the Apache 2.0 license, see [LICENSE](/LICENSE) for
 
 Tessera builds upon the hard work, experience, and lessons from many _many_ folks involved in
 transparency ecosystems over the years.
+
+[tlog-tiles API]: https://c2sp.org/tlog-tiles
+[Static CT API]: https://c2sp.org/static-ct-api