Add yulDetails.optimizerSteps to the standard JSON interface

test/cmdlineTests/standard_optimizer_yulDetails_optimiserSteps/input.json

@@ -0,0 +1,21 @@
+{
+	"language": "Solidity",
+	"sources":
+	{
+		"A":
+		{
+			"content": "pragma solidity >=0.0; contract C { function f() public pure {} }"
+		}
+	},
+	"settings":
+	{
+		"optimizer": {
+			"details": {
+				"yul": true,
+				"yulDetails": {
+					"optimizerSteps": "dhfoDgvulfnTUtnIf\n[    xarrscLM\n]\njmuljuljul VcTOcul jmul"
+				}
+			}
+		}
+	}
+}