improves the code base.
(merge a97d00799a jt/http-auth-proto-v2-fix later to maint).
+ * The include file compat/bswap.h has been updated so that it is safe
+ to (accidentally) include it more than once.
+ (merge 33aa579a55 jk/guard-bswap-header later to maint).
+
+ * The set of header files used by "make hdr-check" unconditionally
+ included sha256/gcrypt.h, even when it is not used, causing the
+ make target to fail. We now skip it when GCRYPT_SHA256 is not in
+ use.
+ (merge f23aa18e7f rj/hdr-check-gcrypt-fix later to maint).
+
+ * The Makefile uses 'find' utility to enumerate all the *.h header
+ files, which is expensive on platforms with slow filesystems; it
+ now optionally uses "ls-files" if working within a repository,
+ which is a trick similar to how all sources are enumerated to run
+ ETAGS on.
+ (merge 92b88eba9f js/find-lib-h-with-ls-files-when-possible later to maint).
+
* Code cleanup, docfix, build fix, etc.
(merge 11f470aee7 jc/test-yes-doc later to maint).
(merge 90503a240b js/doc-symref-in-proto-v1 later to maint).
(merge 1ede45e44b en/merge-options-doc later to maint).
(merge 3e14dd2c8e rd/doc-hook-used-in-sample later to maint).
(merge c271dc28fd nd/no-more-check-racy later to maint).
+ (merge e6e15194a8 yb/utf-16le-bom-spellfix later to maint).
+ (merge bb101aaf0c rd/attr.c-comment-typofix later to maint).
+ (merge 716a5af812 rd/gc-prune-doc-fix later to maint).
+ (merge 50b206371d js/untravis-windows later to maint).
+ (merge dbf47215e3 js/rebase-recreate-merge later to maint).