* Relates-to: #3155 converting duplicted code to fixture

Fixes #3362

Resolves: #3630

Migrate to the new version of Cleo

fix and add several type hints

Add an option to poetry install to install only dev dependencies,
e.g. poetry install --dev-only.

Fixes https://github.com/python-poetry/poetry/issues/2572

Fixes #3577.

This makes `poetry version --short <version>` output only the updated
version number, similarly to `poetry version --short`.

* Remove non-existing --path option
* Add missing options

Co-authored-by: Steph Samson <hello@stephsamson.com>

* Added missing Option in install command description

* Remove python 2.7/3.5 compatibility code

This change removes code, dependencies and tests related to python 2.7
and 3.5 compatibility. The minimum supported runtime python version
for poetry is now 3.6.

* tests: mitigate httpretty urllib incompatibility

Relates-to: #3404

* Fixed the command(deleted the `source` because you don't need `source` in
order to run batch files
* Made code of the table look better, nothing changed in client.

`source`poetry env info --path`/bin/activate`
replaced with:
`source `poetry env info --path`/bin/activate`

Resolves: #477

the built-in function being used does not require comprehension and can work directly with a generator expression

Signed-off-by: Rayan Das <rayandas91@gmail.com>

Signed-off-by: Rayan Das <rayandas91@gmail.com>

Signed-off-by: Rayan Das <rayandas91@gmail.com>

Because `.zprofile` is only run for login shells, it is not used
by graphical terminals. `.zprofile` is also not created by default.

Fixes #2620

Resolves: #3236

\#3236 states that some functions are defined but never used, thus this
PR remove then. While removing them, this also makes sure that there is
no trouble with:
```bash
$ poetry run pytest tests/
$ poetry run pre-commit run --all-files
```
as stated at `CONTRIBUTING.md`.

The functions removed were:

- `poetry/config/config.py`:
  + `_get_validator`

- `poetry/console/commands/config.py`:
  + `_list_setting`
  + `_get_formatted_value`

- `poetry/console/commands/run.py` :
  + `_module`

- `poetry/console/commands/self/update.py :
  + `_bin_path`

- `poetry/mixology/version_solver.py`:
  + `_excludes_single_version`

- `poetry/puzzle/provider.py`:
  + `_formatter_elapsed`

- `poetry/utils/setup_reader.py`:
  + `_is_empty_result`

By removing some of those functions Flack announced that there is no
more need to do some includes, so they were removed too:
- `poetry/mixology/version_solver.py`:
  + `from typing import Any`
  + `from poetry.core.semver import Version`
  + `from poetry.core.semver import VersionRange`
- `poetry/puzzle/provider.py`:
  + `import time`

- ensure tests rely on temporary cache directory
- remove external http call requirement for lock --no-update

Relates-to: #1645

* Add context to caret version constraint documentation

Resolves: #3272