Barcodes - OO replacements, extensible module, tests.

Barcodes - OO replacements, extensible module, tests.

This code is intended to replace current value_builder code in 3.2, but
it does not affect it directly (yet) and is safe to include in 3.0.
This structure will be used to handle more complicated formats, like those
with checkdigits.  Please note that "incremental" format is still STRONGLY
recommended because it will always perform the best, and most flexibly.
The desire to include other information (like branchcode) should compel
the proper use of the barcode generator to print the info ON the barcode,
not IN the barcode.

One of the nicer features of this structure is that you are able to
create a new barcode (of the same type) based on any previous Barcodes object.
That means you can create an array of 51 consecutive barcodes like:
	my $x = C4::Barcodes->new('annual'); # for example
	my @set = ($x);
	for (1..50) {
		push @set, $x=$x->new;
	}
Importantly, this can happen without referencing the database after the
first constructor.

Signed-off-by: Joshua Ferraro <jmf@liblime.com>