Dvc

* dvc: revert checkout to be silly and fast, relink on dvc add though (2882) Suor
* test: refactor tmp dir helper fixtures (2868) Suor
* state: quote % in path (2892) efiop
* external repo: checkout revision before initializing dvc repo (2852) pared
* much grammar such fix (2883) casperdcl
* lengthen bars unless nested/threaded (2857) casperdcl
* Stream progress (2875) casperdcl
* NoRemoteInExternalRepoError: fix message (2881) pared
* Snap (2778) casperdcl
* Support adding directories in google cloud storage remote (2853) skshetry
* s3: Check for all files in given path to match (2873) skshetry
* test: skip non supported remotes fast in api tests (2870) Suor
* GDrive remote support (2551) MaxRis
* s3: ignore empty directories while walking files (2683) mroutis
* remote: http: raise exception when response with error status code (2794) pared
* remote: protect all remote client/session creation code with locks (2863) Suor
* test: refactor & remove redundant test fixtures (2861) danihodovic
* perf: optimize cache listing for local, ssh and hdfs (2836) Suor
* remote: small .save_info()/.get_checksum() cleanup (2835) Suor
* RemoteNotSpecifiedInExternalRepoError: dont pass cause of exception (2854) pared

* Possible fix for 2850. (2856) peper0
* remote: fix remote default call with no arguments (2821) kaiogu
* Fix typos (2855) skshetry
* Fix typo and grammar (2842) skshetry
* Refactor `startswith` with `path_isin` util (2832) skshetry
* dvc: remove unused config paths (2827) Suor
* GS progress for push & pull (2809) casperdcl
* use SI prefixes for progress (2817) casperdcl
* Display path relative to temporary repo when get/import-ing files (2798) skshetry
* perf: switch schema validation library (2796) Suor

* import: intercept and rephrase OutputNotFound message (2777) pared
* perf: optimize yaml parsing for stages (2775) Suor
* makedirs: fix mode flag is being ignored starting from Python 3.7 (2790) shcheklein

* Write test for `tmp_fname` to check if it accepts Path-like and str objects (2808) algomaster99
* Ensure `remove` accepts str and Path-like objects (2795) algomaster99
* perf: a small stage validation optimization (2786) Suor
* Improve `LockError` message (2765) algomaster99
* dvc: remove reorder_python_imports formatter (2787) efiop
* get/import: more meaningful message on NoRemoteError (2759) pared
* test: try using azurite 3.3.0-preview (2785) efiop

Fix windows build.

* Add better heuristic for build detection (2773) n3hrox