capture QR codes from camera and major refactoring

- add GUI for QR code capturing from camera (CV2 is used)
- support different QR readers: ZBAR,QREADER,QREADER_DEEP,CV2,CV2_WECHAT
- support several input files
- add option to ignore duplicate otps
- write warnings and errors to stderr
- add output coloring
- rename project from extract_otp_secret_keys to extract_otp_secrets
- improve help
- clean verbose level output
- use Python type hints and check with mypy
- use f-strings
- clean up code
- add more tests
- calculate code coverage
- use src-layout: move files and folders
- support wheel packing
- enhance README.md
- bugfixes
    * fix -k -
    * fix utf-8 encoding on windows

Pipfile

@@ -8,13 +8,20 @@ protobuf = "*"
 qrcode = "*"
 pillow = "*"
 qreader = "*"
-opencv-python = "*"
+opencv-contrib-python = "*"
+colorama = ">=0.4.6"
+# for macOS: opencv-contrib-python = "<=4.7.0"
+# for PYTHON <= 3.7: typing_extensions = "*"
 
 [dev-packages]
 pytest = "*"
+pytest-mock = "*"
+pytest-cov = "*"
 wheel = "*"
 flake8 = "*"
 pylint = "*"
+mypy = "*"
+types-protobuf = "*"
 
 [requires]
 python_version = "3.11"