Created sample workaround in `example/whatsthis.py`, showing how to
style the `QWhatsThis` widget using `QPalette`, and added a workaround
description to `ISSUES.md`.
Closes#59.
You cannot modify the default link color in a stylesheet, so document
the 2 ways to modify the link color via either the `style` atttibute of
the `a` tag, or using the `QPalette:Link` color role.
Closes#58.
Add shared code between the examples, to reduce the amount of
boilerplate used in each example. Includes shared colors, Qt5/Qt6 compat
definitions, argparsers, and app startup/exec code.
Alex Huszagh