Issue 586: Add tests with keep_line_breaks true

(Currently) only testing for the indentation problem after a newline.

tests/allman/issue0586_keep_line_breaks.d.ref

@@ -0,0 +1,7 @@
+void test()
+{
+    return Struct(
+        foo: field.foo,
+        bar: field.bar,
+        baz: field.baz);
+}

tests/issue0586_keep_line_breaks.args

@@ -0,0 +1 @@
+--keep_line_breaks true

tests/issue0586_keep_line_breaks.d

@@ -0,0 +1,7 @@
+void test()
+{
+    return Struct(
+foo: field.foo,
+bar: field.bar,
+baz: field.baz);
+}

tests/knr/issue0586_keep_line_breaks.d.ref

@@ -0,0 +1,7 @@
+void test()
+{
+    return Struct(
+        foo: field.foo,
+        bar: field.bar,
+        baz: field.baz);
+}

tests/otbs/issue0586_keep_line_breaks.d.ref

@@ -0,0 +1,6 @@
+void test() {
+    return Struct(
+        foo: field.foo,
+        bar: field.bar,
+        baz: field.baz);
+}