[chore] Update Project Status and README formatting (#4146)

* [chore] Update Project Status

* Fornat table

* Update README.md

Co-authored-by: Damien Mathieu <42@dmathieu.com>

---------

Co-authored-by: Damien Mathieu <42@dmathieu.com>
Co-authored-by: Tyler Yahn <MrAlias@users.noreply.github.com>

README.md

@@ -11,22 +11,25 @@ It provides a set of APIs to directly measure performance and behavior of your s
 
 ## Project Status
 
-| Signal  | Status     | Project |
-| ------- | ---------- | ------- |
-| Traces  | Stable     | N/A     |
-| Metrics | Stable     | N/A     |
-| Logs    | Frozen [1] | N/A     |
+| Signal  | Status     | Project               |
+|---------|------------|-----------------------|
+| Traces  | Stable     | N/A                   |
+| Metrics | Mixed [1]  | [Go: Metric SDK (GA)] |
+| Logs    | Frozen [2] | N/A                   |
 
-- [1]: The Logs signal development is halted for this project while we develop both Traces and Metrics.
+[Go: Metric SDK (GA)]: https://github.com/orgs/open-telemetry/projects/34
+
+- [1]: [Metrics API](https://pkg.go.dev/go.opentelemetry.io/otel/metric) is Stable. [Metrics SDK](https://pkg.go.dev/go.opentelemetry.io/otel/sdk/metric) is Beta.
+- [2]: The Logs signal development is halted for this project while we stablize the Metrics SDK.
    No Logs Pull Requests are currently being accepted.
 
-Progress and status specific to this repository is tracked in our local
+Progress and status specific to this repository is tracked in our
 [project boards](https://github.com/open-telemetry/opentelemetry-go/projects)
 and
 [milestones](https://github.com/open-telemetry/opentelemetry-go/milestones).
 
 Project versioning information and stability guarantees can be found in the
-[versioning documentation](./VERSIONING.md).
+[versioning documentation](VERSIONING.md).
 
 ### Compatibility
 
@@ -49,7 +52,7 @@ stop ensuring compatibility with these versions in the following manner:
 Currently, this project supports the following environments.
 
 | OS      | Go Version | Architecture |
-| ------- | ---------- | ------------ |
+|---------|------------|--------------|
 | Ubuntu  | 1.20       | amd64        |
 | Ubuntu  | 1.19       | amd64        |
 | Ubuntu  | 1.20       | 386          |
@@ -97,12 +100,12 @@ export pipeline to send that telemetry to an observability platform.
 All officially supported exporters for the OpenTelemetry project are contained in the [exporters directory](./exporters).
 
 | Exporter                              | Metrics | Traces |
-| :-----------------------------------: | :-----: | :----: |
-| [Jaeger](./exporters/jaeger/)         |         | ✓      |
-| [OTLP](./exporters/otlp/)             | ✓       | ✓      |
-| [Prometheus](./exporters/prometheus/) | ✓       |        |
-| [stdout](./exporters/stdout/)         | ✓       | ✓      |
-| [Zipkin](./exporters/zipkin/)         |         | ✓      |
+|---------------------------------------|:-------:|:------:|
+| [Jaeger](./exporters/jaeger/)         |         |   ✓    |
+| [OTLP](./exporters/otlp/)             |    ✓    |   ✓    |
+| [Prometheus](./exporters/prometheus/) |    ✓    |        |
+| [stdout](./exporters/stdout/)         |    ✓    |   ✓    |
+| [Zipkin](./exporters/zipkin/)         |         |   ✓    |
 
 ## Contributing