Build 1

• (TB Drivers) Ship the l10n milestone
• (TB Drivers) Submit to Ship It
• Push to mirrors
• Publish in Balrog
• Post-release tasks

Issues

• repack_2/10 failed for Thunderbird 38.7.1 build1 on macosx64
• repack_5/10 failed for Thunderbird 38.7.1 build1 on macosx64
• repack_6/10 failed for Thunderbird 38.7.1 build1 on macosx64
• repack_9/10 failed for Thunderbird 38.7.1 build1 on macosx64
• Thunderbird 38.7.1 SHA512SUMS file is incorrect for one l10n chunk on mac bug 1260986