1.0.0a0

• run: use multistage dvcfiles by default (#3740) @efiop
• run: remove deprecated -y|--yes (#3737) @efiop
• ui: simplify/shorten error messages (#3730) @skshetry
• plot: completion for zsh (#3733) @pared
• cache: rename .dvc/cache/run to .dvc/cache/runs (#3732) @efiop
• Make comparisons in is_cached independent of order (#3731) @skshetry
• run: add to .gitignore on --no-exec (#3729) @efiop
• diff: make output consistent with other diff commands (#3727) @efiop
• status: --recursive flag (#3726) @nik123
• dvc: move temporary files to .dvc/tmp (#3725) @efiop
• stage: rename .dvc/cache/stages -> .dvc/cache/run (#3724) @efiop
• progress: add postfix info to avoid overwriting desc (#3721) @casperdcl
• Metrics - plotting for multiple revisions initial (#3577) @pared
• stage: cache: use lockfiles (#3713) @efiop
• dump: deterministic lockfile dump (#3711) @skshetry
• dvc: rename pipelines.yaml -> dvc.yaml (#3710) @efiop
• run: try to save deps before running the command (#3709) @efiop
• serialize: use checksums that are already saved (#3708) @efiop
• remote: adjust traverse threshold multiplier (#3705) @pmrowla
• dvc: introduce local stage cache (#3603) @efiop
• gdrive: fix multi-remote workflow, cont. cleanup (#3686) @shcheklein
• setup: relax python-dateutil pip version constraint to include v2.8.2. #3701 (#3702) @dchichkov
• tag: getting rid of it (#3699) @skshetry
• remote.ssh: suppress paramiko logging (#3675) @pmrowla
• dvc: implement params support for pipeline file (#3694) @skshetry
• refactor: dvc/output class names unification (#3695) @nik123
• repo: use reverse post-order DFS in repro --downstream (#3689) @pmrowla
• remote: use string paths over PathInfo for performance reasons (#3672) @pmrowla
• dvc: implement multistage dvcfile (#3676) @skshetry
• refactor: dvc/dependency class names unification (#3688) @nik123
• refactor: dvc/remotes class names unification (#3684) @nik123
• progress: add main bars (#3594) @casperdcl
• git: is_tracked: use ls_files instead of walking the index (#3677) @efiop
• flake8: fix ambiguous var names (#3674) @pmrowla
• Convert all paths in config to posix-style (#3665) @charlesbaynham
• output: use strings instead of PathInfo for performance reasons (#3663) @pmrowla
• metrics: rework metrics implementation (#3658) @efiop
• Fix repro duplicating effort while checking steps #3644 (#3645) @charlesbaynham
• metrics diff error message in --no-scm projects (#3650) @karajan1001
• gc: don't forget to load remote index (#3660) @efiop
• remote: locally index list of checksums available on cloud remotes (#3634) @pmrowla
• refactor: extract stage loading outside of dvcfile (#3655) @skshetry
• tests: test_directories (#3649) @nik123
• Specify cmd arg names (metavars), et al. (#3626) @jorgeorpinel
• scm: git: clone: add progress (#3595) @casperdcl
• dvc: implement multi-stage dvcfile (#3584) @skshetry
• tests: add some DvcTree unit tests (#3640) @efiop
• dvc: introduce DvcTree (#3639) @efiop
• remote: don't use PathInfo.from_posix (#3637) @efiop
• remote config validation (#3628) @karajan1001
• params: diff: introduce --all (#3631) @efiop
• remote: use .dir checksum existence to infer file contents existence (#3632) @pmrowla
• refactor: extract stage's relationship with Dvcfile out from Stage (#3619) @skshetry
• Updates latest version of PyDrive2 (#3624) @mribeirodantas
• stage: resolve stage path before creating the stage (#3630) @efiop
• run: remove deprecated --cwd (#3623) @efiop