Specify allowed EAN extensions as a hint.
Merge pull request #63 from embarkmobile/ean-extension

Specify allowed EAN extensions as a hint
Issue #63 : minor formatting and doc changes
Issue #67 : Avoid rare AIOOBE on PDF417 misread
Handle VEVENT with malformed GEO
Build barcode from left to right instead of right to left.
Merge pull request #70 from chriskeyring/master

Code 39 Barcodes Generated Backwards
Merge remote-tracking branch 'source/master'