[13324] Make Code39Reader.ALPHABET_STRING public
[13324] Make Code39Reader.ALPHABET_STRING public

git-tfs-id: [https://tfs.codeplex.com/tfs/TFS05/]$/ZXingNet/trunk;C89358

DHMechatronicAG/ZXing.Net,bsoja/ZXing.Net,bsoja/ZXing.Net,micjahn/ZXing.Net,DHMechatronicAG/ZXing.Net,DHMechatronicAG/ZXing.Net,micjahn/ZXing.Net,bsoja/ZXing.Net,micjahn/ZXing.Net