Added quoted multi-line string test.

decode_test.go

diff --git a/decode_test.go b/decode_test.go
index d68d546..89a9fdb 100644
--- a/decode_test.go
+++ b/decode_test.go
@@ -267,6 +267,9 @@
 	{
 		"'1': '\"2\"'",
 		map[interface{}]interface{}{"1": "\"2\""},
+	}, {
+		"v:\n- A\n- 'B\n\n  C'\n",
+		map[string][]string{"v": []string{"A", "B\nC"}},
 	},
 
 	// Explicit tags.

encode_test.go

diff --git a/encode_test.go b/encode_test.go
index 78e3112..0d34d88 100644
--- a/encode_test.go
+++ b/encode_test.go
@@ -85,6 +85,9 @@
 		map[string][]string{"v": []string{"A", "B"}},
 		"v:\n- A\n- B\n",
 	}, {
+		map[string][]string{"v": []string{"A", "B\nC"}},
+		"v:\n- A\n- 'B\n\n  C'\n",
+	}, {
 		map[string][]interface{}{"v": []interface{}{"A", 1, map[string][]int{"B": []int{2, 3}}}},
 		"v:\n- A\n- 1\n- B:\n  - 2\n  - 3\n",
 	}, {