Format and lint codes and fix packaging (#125)

* add: configure files (setup.py->setup.py+setup.cfg+pyproject.toml)

* add: __download_url__

* format with black and isort

* fix: flake8 section in setup.cfg

* add: E501 to flake ignore

* fix: metadata.name does not accept attr

* fix: merge __version__.py into __init__.py

* fix: flake8 errors in tests/

* fix: datetime.datetime -> datetime

* fix: banner

* fix: ignore W605 for banner

* fix: way to install deps in CI

* add: versem to setuptools

* fix: drop python<=3.6 (#126) from package and CI

setup.cfg

@@ -1,7 +1,67 @@
 [metadata]
-description-file = README.md
-license_file = LICENSE
+name = waybackpy
+version = attr: waybackpy.__version__
+description = attr: waybackpy.__description__
+long_description = file: README.md
+long_description_content_type = text/markdown
+license = attr: waybackpy.__license__
+author = attr: waybackpy.__author__
+author_email = attr: waybackpy.__author_email__
+url = attr: waybackpy.__url__
+download_url = attr: waybackpy.__download_url__
+project_urls =
+    Documentation = https://github.com/akamhy/waybackpy/wiki
+    Source = https://github.com/akamhy/waybackpy
+    Tracker = https://github.com/akamhy/waybackpy/issues
+keywords =
+    Archive Website
+    Wayback Machine
+    Internet Archive
+    Wayback Machine CLI
+    Wayback Machine Python
+    Internet Archiving
+    Availability API
+    CDX API
+    savepagenow
+classifiers =
+    Development Status :: 4 - Beta
+    Intended Audience :: Developers
+    Natural Language :: English
+    License :: OSI Approved :: MIT License
+    Programming Language :: Python
+    Programming Language :: Python :: 3
+    Programming Language :: Python :: 3.7
+    Programming Language :: Python :: 3.8
+    Programming Language :: Python :: 3.9
+    Programming Language :: Python :: 3.10
+    Programming Language :: Python :: Implementation :: CPython
+
+[options]
+packages = find:
+python_requires = >= 3.7
+install_requires =
+    click
+    requests
+
+[options.extras_require]
+dev =
+    black
+    codecov
+    flake8
+    mypy
+    pytest
+    pytest-cov
+    setuptools>=46.4.0
+
+
+[options.entry_points]
+console_scripts =
+    waybackpy = waybackpy.cli:main
+
+[isort]
+profile = black
 
 [flake8]
+indent-size = 4
 max-line-length = 88
-extend-ignore = E203,W503
+extend-ignore = E203,W503,E501,W605