Markdown linter (#1309)

* Add markdown linting

- add linter default rules
- adapt rules to current code
- fix the code for linting to pass
- add CI check

fix #1243

* Fix markdown for Substrate
* Fix tooling install
* Fix workflow
* Add documentation
* Remove trailing spaces
* Update .github/.markdownlint.yaml

Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>
* Fix mangled markdown/lists
* Fix captalization issues on known words

substrate/client/telemetry/README.md

@@ -1,6 +1,6 @@
 # sc-telemetry
 
-Substrate's client telemetry is a part of substrate that allows ingesting telemetry data
+Substrate's client telemetry is a part of Substrate that allows ingesting telemetry data
 with for example [Polkadot telemetry](https://github.com/paritytech/substrate-telemetry).
 
 It works using Tokio's [tracing](https://github.com/tokio-rs/tracing/) library. The telemetry
@@ -9,8 +9,8 @@ tracing `Layer`. This layer will then send the data through an asynchronous chan
 background task called [`TelemetryWorker`] which will send the information to the configured
 remote telemetry servers.
 
-If multiple substrate nodes are running in the same process, it uses a `tracing::Span` to
-identify which substrate node is reporting the telemetry. Every task spawned using sc-service's
+If multiple Substrate nodes are running in the same process, it uses a `tracing::Span` to
+identify which Substrate node is reporting the telemetry. Every task spawned using sc-service's
 `TaskManager` automatically inherit this span.
 
 Substrate's nodes initialize/register with the [`TelemetryWorker`] using a [`TelemetryHandle`].