Typing: annotate text_layout and extend Text/Edit

[penguinolog]

• Canvas: do not accept any arguments in the constructor. Arguments deprecated many years ago, renamed error was raise before.
• StandardTextLayout: split calculate_text_segments scenario for clip and ellipsis from any and space. Extremely long methods with 2 main branches. Use human-friendly variable naming.
• Text/Edit: In several methods intentionally do not mark bytes as valid argument: Due to the amount of transcoding, str is absolute priority

Checklist

• I've ensured that similar functionality has not already been implemented
• I've ensured that similar functionality has not earlier been proposed and declined
• I've branched off the master or python-dual-support branch
• I've merged fresh upstream into my branch recently
• I've ran tox successfully in local environment
• I've included docstrings and/or documentation and/or examples for my code (if this is a new feature)

[coveralls]

Pull Request Test Coverage Report for Build 7812944319

• -8 of 109 (92.66%) changed or added relevant lines in 4 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage increased (+0.003%) to 70.888%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
urwid/text_layout.py	84	92	91.3%

Files with Coverage Reduction	New Missed Lines	%
urwid/text_layout.py	1	87.5%

Totals
Change from base Build 7811498686:	0.003%
Covered Lines:	8773
Relevant Lines:	12461

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💛 - Coveralls