Update Usage.md

TonioMacaronio · web-flow · commit b9d92a629051 · 2018-09-28T19:07:21.000+03:00
diff --git a/Documentation/Usage.md b/Documentation/Usage.md
@@ -594,5 +594,3 @@ func getBlockNumber(completion: @escaping (String?) -> Void) {
     }
 }
 ```
-
-### Get Block Gas Price

Original file line number	Diff line number	Diff line change
`@@ -594,5 +594,3 @@ func getBlockNumber(completion: @escaping (String?) -> Void) {`
`594`	`594`	`}`
`595`	`595`	`}`
`596`	`596`	```
`597`		`-`
`598`		`-### Get Block Gas Price`