More style flexibility in chat rendering

[nanypoco]

Checklist

• I have checked the issue page for duplicates
• I am running the latest version (download here)

Write your feature request here

• Allow font and detailed style settings for each of timestamps, user names, messages, etc.
• Change behavior of font selection for user's name (display_name).
  Currently, when display name contains non-ascii characters, a fallback font is forced to be used, regardless of whether the configured message font contains non-ascii glyphs.
  As with messages, determine whether the font contains glyphs for each character, and if necessary, allow selection of the processing done in the current code.
• Specify the drawing content in tag format.
  For example "<timestamp> <badges><displayname>: <message>".