Add markup support for FormattedText

[mrDIMAS]

FormattedText does not have an ability to change color of single letters, change their size, etc. I propose to add simple markup support with tags for that. FormattedText then should parse markup and change behavior accordingly.

[b-guild]

What markup language should we use? Will there be a way for the parser to find available fonts? Will the parser be configurable with custom tags?

[mrDIMAS]

I think it could be simple BB codes, for example this is how it done in WPF analog in C++.