Add custom QZ Tray fork with pairing key authentication

- Custom fork of QZ Tray 2.2.x with certificate validation bypassed
- Implemented pairing key (HMAC) authentication as replacement
- Modified files: PrintSocketClient.java (certificate check disabled)
- New files: PairingAuth.java, PairingConfigDialog.java
- Excluded build artifacts (out/, lib/javafx*) from repository
- Library JARs included for dependency management

tray/assets/signing/sign-message.pl

@@ -0,0 +1,52 @@
+#!/usr/bin/perl
+#
+# Echoes the signed message and exits
+# usage:  ./sign-message.pl "test"
+#
+#########################################################
+#             WARNING   WARNING   WARNING               #
+#########################################################
+#                                                       #
+# This file is intended for demonstration purposes      #
+# only.                                                 #
+#                                                       #
+# It is the SOLE responsibility of YOU, the programmer  #
+# to prevent against unauthorized access to any signing #
+# functions.                                            #
+#                                                       #
+# Organizations that do not protect against un-         #
+# authorized signing will be black-listed to prevent    #
+# software piracy.                                      #
+#                                                       #
+# -QZ Industries, LLC                                   #
+#                                                       #
+#########################################################
+
+# RSA Crypto libs provided by:
+#     Debian: libcrypt-openssl-rsa-perl
+#     RedHat: perl-Crypt-OpenSSL-RSA
+use Crypt::OpenSSL::RSA;
+use MIME::Base64 qw(encode_base64);
+
+# Get first argument passed to script
+my $request = $ARGV[0];
+
+# Path to the private key
+my $pem_file = "private-key.pem";
+
+# Read private key
+my $private_key = do {
+    local $/ = undef;
+    open my $fh, "<", $pem_file
+        or die "could not open $file: $!";
+    <$fh>;
+};
+
+# Load private key
+my $rsa = Crypt::OpenSSL::RSA->new_private_key($private_key);
+
+# Create signature
+$rsa->use_sha512_hash(); # use_sha1_hash for QZ Tray 2.0 and older
+my $sig = encode_base64($rsa->sign($request));
+
+print $sig;