[SMTChecker] User timeout option

test/cmdlineTests/standard_model_checker_timeout_wrong_key/input.json

@@ -0,0 +1,15 @@
+{
+	"language": "Solidity",
+	"sources":
+	{
+		"A":
+		{
+			"content": "// SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0;\npragma experimental SMTChecker;\ncontract C { function f(uint x) public pure { assert(x > 0); } }"
+		}
+	},
+	"modelCheckerSettings":
+	{
+		"engine": "chc",
+		"atimeout": 1
+	}
+}

test/cmdlineTests/standard_model_checker_timeout_wrong_key/output.json

@@ -0,0 +1 @@
+{"errors":[{"component":"general","formattedMessage":"Unknown key \"atimeout\"","message":"Unknown key \"atimeout\"","severity":"error","type":"JSONError"}]}