Allowing vertical barcode printing

Adding new tag attribute to print the barcode in vertical position
Merge pull request #140 from glomium/master

fixed issue #59
Merge pull request #139 from zot24/master

Allowing vertical barcode printing
Fixed canvas to new origin

Moving our canvas to the new origin when rotate it
Merge branch 'master' of https://github.com/chrisglass/xhtml2pdf
Merge pull request #142 from zot24/master

Fixed canvas to new origin