Make packaging the (considerable amount of) documentation optional.

Without docs, the resulting binary package is 4MB instead of 22MB.

databases/db4/Makefile

@@ -1,4 +1,4 @@
-# $NetBSD: Makefile,v 1.64 2013/02/24 06:55:29 obache Exp $
+# $NetBSD: Makefile,v 1.65 2013/03/01 16:10:23 jperkin Exp $
 #
 # NOTE:
 # When updating this package, a change in the minor (4.n -> 4.(n+1))
@@ -38,11 +38,14 @@ LIBSO_LIBS.SunOS+=	-lnsl -lrt
 CONFIGURE_ENV+=		LIBSO_LIBS=${LIBSO_LIBS:Q}
 
 .include "../../mk/bsd.prefs.mk"
+
 PLIST_VARS+=		norm_so
 .if ${OPSYS} != "Cygwin"
 PLIST.norm_so=		yes
 .endif
 
+.include "options.mk"
+
 # DB4 only want pthreads because it's really after POSIX 1003.1
 # inter-process mutexes.  In this case, we only care to use the native
 # threads.

databases/db4/options.mk

@@ -0,0 +1,22 @@
+# $NetBSD: options.mk,v 1.5 2013/03/01 16:10:23 jperkin Exp $
+
+PKG_OPTIONS_VAR=	PKG_OPTIONS.db4
+
+PKG_SUPPORTED_OPTIONS=	doc
+PKG_SUGGESTED_OPTIONS=	doc
+
+PLIST_SRC+=		PLIST
+
+.include "../../mk/bsd.options.mk"
+
+###
+### Install documentation files
+###
+.if empty(PKG_OPTIONS:Mdoc)
+SUBST_CLASSES+=		docs
+SUBST_STAGE.docs=	pre-configure
+SUBST_FILES.docs=	dist/Makefile.in
+SUBST_SED.docs=		-e '/^library_install:/s, install_docs,,'
+.else
+PLIST_SRC+=		PLIST.docs
+.endif