Update AutoValue changelog with 1.5 changes.
Update AutoValue changelog with 1.5 changes.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=165322602

MaTriXy/auto,MaTriXy/auto,google/auto,eamonnmcmanus/auto,google/auto,google/auto,eamonnmcmanus/auto,eamonnmcmanus/auto