Move source properties out to a module

* module/ice-9/source-properties.scm: New file, providing the
source-properties API, as well as a replacement for `read' that always
attaches source properties, regardless of the 'positions option on the
port.

* am/bootstrap.am (SOURCES): Add the new file.

* libguile/srcprop.c:
* libguile/srcprop.h: Remove.

* libguile/Makefile.am (libguile_@GUILE_EFFECTIVE_VERSION@_la_SOURCES):
(DOT_X_FILES):
(DOT_DOC_FILES):
(modinclude_HEADERS):
* libguile.h: Remove srcprop.h.

* libguile/deprecated.c:
* libguile/deprecated.h: Add deprecation shims for srcprop.h interface.

* libguile/backtrace.c:
* libguile/debug.c:
* libguile/eval.c:
* libguile/init.c:
* libguile/memoize.c:
* libguile/promises.c:
* libguile/read.c:
* libguile/syntax.c: Remove needless srcprop.h includes.

* module/ice-9/boot-9.scm: Reorder some definitions so that deprecated
modules can use the (system syntax internal) module.

* module/ice-9/deprecated.scm: Add shims for Scheme source-properties
interface.

* module/ice-9/read.scm (read): Never attach source properties.  Users
that want source can use read-syntax.

* module/language/cps.scm:
* module/language/cps/spec.scm:
* module/language/ecmascript/compile-tree-il.scm:
* module/language/elisp/compile-tree-il.scm:
* module/language/elisp/lexer.scm:
* module/language/elisp/parser.scm:
* module/language/tree-il.scm:
* module/language/tree-il/spec.scm:
* module/language/wisp.scm:
* module/system/base/lalr.scm:
* test-suite/tests/elisp-reader.test:
* test-suite/tests/reader.test:
* test-suite/tests/srcprop.test:
* test-suite/tests/srfi-105.test:
* test-suite/tests/srfi-119.test: Use the (ice-9 source-properties)
module to get access to source properties.

libguile/syntax.c

@@ -31,7 +31,6 @@
 #include "modules.h"
 #include "pairs.h"
 #include "ports.h"
-#include "srcprop.h"
 #include "threads.h"
 #include "variable.h"
 #include "vectors.h"