Create src/fe_utils/, and move stuff into there from pg_dump's dumputils.

Per discussion, we want to create a static library and put the stuff into
it that until now has been shared across src/bin/ directories by ad-hoc
methods like symlinking a source file.  This commit creates the library and
populates it with a couple of files that contain the widely-useful portions
of pg_dump's dumputils.c file.  dumputils.c survives, because it has some
stuff that didn't seem appropriate for fe_utils, but it's significantly
smaller and is no longer referenced from any other directory.

Follow-on patches will move more stuff into fe_utils.

The Mkvcbuild.pm hacking here is just a best guess; we'll see how the
buildfarm likes it.

src/fe_utils/simple_list.c

@@ -0,0 +1,116 @@
+/*-------------------------------------------------------------------------
+ *
+ * Simple list facilities for frontend code
+ *
+ * Data structures for simple lists of OIDs and strings.  The support for
+ * these is very primitive compared to the backend's List facilities, but
+ * it's all we need in, eg, pg_dump.
+ *
+ *
+ * Portions Copyright (c) 1996-2016, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/fe_utils/simple_list.c
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres_fe.h"
+
+#include "fe_utils/simple_list.h"
+
+
+/*
+ * Append an OID to the list.
+ */
+void
+simple_oid_list_append(SimpleOidList *list, Oid val)
+{
+	SimpleOidListCell *cell;
+
+	cell = (SimpleOidListCell *) pg_malloc(sizeof(SimpleOidListCell));
+	cell->next = NULL;
+	cell->val = val;
+
+	if (list->tail)
+		list->tail->next = cell;
+	else
+		list->head = cell;
+	list->tail = cell;
+}
+
+/*
+ * Is OID present in the list?
+ */
+bool
+simple_oid_list_member(SimpleOidList *list, Oid val)
+{
+	SimpleOidListCell *cell;
+
+	for (cell = list->head; cell; cell = cell->next)
+	{
+		if (cell->val == val)
+			return true;
+	}
+	return false;
+}
+
+/*
+ * Append a string to the list.
+ *
+ * The given string is copied, so it need not survive past the call.
+ */
+void
+simple_string_list_append(SimpleStringList *list, const char *val)
+{
+	SimpleStringListCell *cell;
+
+	cell = (SimpleStringListCell *)
+		pg_malloc(offsetof(SimpleStringListCell, val) +strlen(val) + 1);
+
+	cell->next = NULL;
+	cell->touched = false;
+	strcpy(cell->val, val);
+
+	if (list->tail)
+		list->tail->next = cell;
+	else
+		list->head = cell;
+	list->tail = cell;
+}
+
+/*
+ * Is string present in the list?
+ *
+ * If found, the "touched" field of the first match is set true.
+ */
+bool
+simple_string_list_member(SimpleStringList *list, const char *val)
+{
+	SimpleStringListCell *cell;
+
+	for (cell = list->head; cell; cell = cell->next)
+	{
+		if (strcmp(cell->val, val) == 0)
+		{
+			cell->touched = true;
+			return true;
+		}
+	}
+	return false;
+}
+
+/*
+ * Find first not-touched list entry, if there is one.
+ */
+const char *
+simple_string_list_not_touched(SimpleStringList *list)
+{
+	SimpleStringListCell *cell;
+
+	for (cell = list->head; cell; cell = cell->next)
+	{
+		if (!cell->touched)
+			return cell->val;
+	}
+	return NULL;
+}