Support of encrypted xlsx files

Added support for reading encrypted xlsx files in accordance with [MS-OFFCRYPTO]: Office Document Cryptography Structure
https://msdn.microsoft.com/en-us/library/cc313071(v=office.12).aspx
Support of standard and agile encryption

modified:   lib/Spreadsheet/ParseXLSX.pm
new file:   t/data/encryption-agile-123q.xlsx
new file:   t/data/encryption-standard-default-password.xlsx
new file:   t/encryption.t

3 files changed, 30 insertions, 0 deletions

diff --git a/t/data/encryption-agile-123q.xlsx b/t/data/encryption-agile-123q.xlsx
new file mode 100644
index 0000000..be3b561
--- /dev/null
+++ b/t/data/encryption-agile-123q.xlsx
diff --git a/t/data/encryption-standard-default-password.xlsx b/t/data/encryption-standard-default-password.xlsx
new file mode 100644
index 0000000..a863c1b
--- /dev/null
+++ b/t/data/encryption-standard-default-password.xlsx
diff --git a/t/encryption.t b/t/encryption.t
new file mode 100644
index 0000000..6def0f4
--- /dev/null
+++ b/t/encryption.t
@@ -0,0 +1,30 @@
+#!/usr/bin/env perl
+use strict;
+use warnings;
+use Test::More;
+
+use lib::Spreadsheet::ParseXLSX;
+
+my $parser = Spreadsheet::ParseXLSX->new();
+my $workbook = $parser->parse("t/data/encryption-agile-123q.xlsx", {password => '123q'});
+
+my $worksheet;
+my $cell;
+
+$worksheet = $workbook->worksheet(0);
+ok(defined($workbook));
+
+$cell = $worksheet->get_cell(1, 1);
+ok(defined($cell) && $cell->value() eq 'abcdefgABCDEFG');
+
+
+open FH, "t/data/encryption-standard-default-password.xlsx";
+$workbook = $parser->parse(\*FH);
+
+ok(defined($workbook));
+
+$worksheet = $workbook->worksheet(0);
+$cell = $worksheet->get_cell(22, 8);
+ok(defined($cell) && $cell->value() == 1911);
+
+done_testing;