1. Multiple test improvements;
2. Fix a bug in dvc repro, when callback stages were not reproduced and instead a build cache was used;
3. dvc status with --remote now implies --cloud;
4. Raise exception when output/dependency doesn't exist. Previously this was handled properly only for local outputs/dependencies;
5. Use temporary file as an intermediary step when uploading to ssh remote to prevent cache corruption;
6. Use cache directory mtime/inode/size to do cache validation faster;
7. Support dvc run --wdir as a way to run dvc file command from a directory that doesn't match dvc file location;
8. Gracefully handle a case when a progress bar is interrupted with a prompt;
9. Support dvc add for symlinks that point to a location within or outside the current project;
10. Multiple code refactorings;