Extend __repr__ and rich repr for the sized containers

[penguinolog]

Due to extremely hard to debug tracebacks,
add __repr__ details
and full details for rich.print/rich.pretty.pretty_repr

• Columns
• Pile
• GridFlow
• Frame
• Overlay
• Padding

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 8066999827

Details

• -4 of 23 (82.61%) changed or added relevant lines in 5 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.08%) to 72.502%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
urwid/widget/overlay.py	9	13	69.23%

Totals
Change from base Build 8050739147:	-0.08%
Covered Lines:	9082
Relevant Lines:	12607

---

💛 - Coveralls