tang: Update to version 7

Added License information.

Cleaned up Makefile for consistency between packages.

Added numerical prefixes to the patches for clarity.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

utils/tang/patches/020-no-systemd.patch

@@ -0,0 +1,35 @@
+--- a/configure.ac
++++ b/configure.ac
+@@ -27,32 +27,6 @@ AC_CHECK_LIB([http_parser], [http_parser_execute],
+              [AC_MSG_ERROR([http-parser required!])])
+ 
+ PKG_CHECK_MODULES([jose], [jose >= 8])
+-PKG_CHECK_MODULES([systemd], [systemd])
+-
+-AC_ARG_WITH([systemdsystemunitdir],
+-            [AS_HELP_STRING([--with-systemdsystemunitdir=DIR], [Directory for systemd service files])],
+-            [],
+-            [with_systemdsystemunitdir=$($PKG_CONFIG --variable=systemdsystemunitdir systemd)])
+-
+-AC_SUBST([systemdsystemunitdir], [$with_systemdsystemunitdir])
+-
+-for ac_prog in systemd-socket-activate systemd-activate; do
+-    AC_CHECK_PROG([SD_ACTIVATE], [$ac_prog], [$as_dir/$ac_prog], [],
+-		  [$PATH$PATH_SEPARATOR$($PKG_CONFIG --variable=systemdutildir systemd)])
+-    test -n "$SD_ACTIVATE" && break
+-done
+-
+-test -n "$SD_ACTIVATE" || AC_MSG_ERROR([systemd-socket-activate required!])
+-
+-AC_MSG_CHECKING([systemd-socket-activate inetd flag])
+-if $SD_ACTIVATE --help | grep -q inetd; then
+-    SD_ACTIVATE="$SD_ACTIVATE --inetd"
+-    AC_MSG_RESULT([--inetd])
+-else
+-    AC_MSG_RESULT([(default)])
+-fi
+-
+-AC_SUBST(SD_ACTIVATE)
+ 
+ TANG_CFLAGS="\
+ -Wall \