stunnel: Bring it back at v5.10

From: Michael Haas <haas@computerlinguist.org>

* init script no longer creates certificates (consider client mode as use
  case)
* patches/010_fix_getnameinfo.patch: Fix getnameinfo signature
* patches/011_disable_ssp_linking.patch: Disable -fstack-protector as it
  is not always available in OpenWRT
* old patches (in oldpackages) no longer necessary
* remove libwrap dependency
* remove libpthread dependency
* respect CONFIG_IPV6
* init script uses procd
* sample stunnel.conf runs in client mode - prevents start failure,
  does not require cert

Possible enhancement: automatically generate certificate as done in
uhttpd. However, as client mode is a possible use case, I'd rather not.
Additionally, stunnel may use several certs with user-defined locations
and we can't easily set a cert location via command-line args.

The package is based on
https://sites.google.com/site/twisteroidambassador/openwrt/stunnel

Signed-off-by: Michael Haas <haas@computerlinguist.org>

net/stunnel/files/stunnel.conf

@@ -0,0 +1,45 @@
+; Drop privileges
+setuid = nobody 
+setgid = nogroup
+
+; When running under procd, stay in foreground
+foreground = yes
+
+; Don't log to stderr, use syslog
+syslog = yes
+
+; 1-7. Use 7 for greatest verbosity
+;debug = 5
+
+; Starting here, enter your services or uncomment the examples
+
+; Example:
+; If your local httpd does not support HTTPS, use stunnel in remote
+; mode to forward TLS connections coming in on port 443 to non-TLS
+; on port 80.
+; Make sure that the cert is available.
+;[httpd]
+;accept = 443
+;connect = 127.0.0.1:80
+;cert = /etc/stunnel/stunnel.pem
+
+; Example:
+; If your local email client does not support TLS,
+; use stunnel in client mode to forward non-TLS connections on
+; port 143 to TLS-enabled servername:993.
+;[imap]
+;client = yes
+;accept = 143
+;connect = servername:993
+; Disable peer verification - be sure to understand the limitations of peer
+; verification in stunnel when enabling.
+;verify = 0
+
+; Default client section:
+; stunnel requires at least one section to start successfully.
+; You can safely remove this section once you have configured
+; your own. We use client mode here as server requires a certificate.
+[dummy]
+client = yes
+accept = localhost:6000
+connect = localhost:6001