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/include/fe_utils/string_utils.h

@@ -0,0 +1,51 @@
+/*-------------------------------------------------------------------------
+ *
+ * String-processing utility routines for frontend code
+ *
+ * Assorted utility functions that are useful in constructing SQL queries
+ * and interpreting backend output.
+ *
+ *
+ * Portions Copyright (c) 1996-2016, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/fe_utils/string_utils.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef STRING_UTILS_H
+#define STRING_UTILS_H
+
+#include "libpq-fe.h"
+#include "pqexpbuffer.h"
+
+#define atooid(x)  ((Oid) strtoul((x), NULL, 10))
+
+/* Global variables controlling behavior of fmtId() and fmtQualifiedId() */
+extern int	quote_all_identifiers;
+extern PQExpBuffer (*getLocalPQExpBuffer) (void);
+
+/* Functions */
+extern const char *fmtId(const char *identifier);
+extern const char *fmtQualifiedId(int remoteVersion,
+			   const char *schema, const char *id);
+
+extern void appendStringLiteral(PQExpBuffer buf, const char *str,
+					int encoding, bool std_strings);
+extern void appendStringLiteralConn(PQExpBuffer buf, const char *str,
+						PGconn *conn);
+extern void appendStringLiteralDQ(PQExpBuffer buf, const char *str,
+					  const char *dqprefix);
+extern void appendByteaLiteral(PQExpBuffer buf,
+				   const unsigned char *str, size_t length,
+				   bool std_strings);
+
+extern bool parsePGArray(const char *atext, char ***itemarray, int *nitems);
+
+extern bool processSQLNamePattern(PGconn *conn, PQExpBuffer buf,
+					  const char *pattern,
+					  bool have_where, bool force_escape,
+					  const char *schemavar, const char *namevar,
+					  const char *altnamevar, const char *visibilityrule);
+
+#endif   /* STRING_UTILS_H */