When running .NET Core 2.1 or .NET Framework 4.6.1, the used regex for
detecting Windows 10 TrueColor support does not match the OSDescription.
The reason for this is because on those frameworks the description has
trailing whitespaces, but they do not on .NET Core 3.1.
This commit updates the regex to ignore any trailing whitespaces.
- A `Text` object should not be able to justify itself.
All justification needs to be done by a parent.
- Apply colors and styles to part of a `Text` object
- Markup parser should return a `Text` object
