Support markup tags (optionally) when displaying posts
Defaults to "Off" ("No") and can be set per-sub-board to either: - "Yes" parse/apply markup style to displayed message text while still displaying the markup tags - "Hide" parse/apply markup style to displayed message text and hide (don't display) the markup tags - "No", treat marked-up messages the same as any other message text, same as before. The supported Markup tags at this time are: #bold text# /Italicized text/ _underlined text_ #inverse text# Now, ANSI-BBS terminals (and Synchronet) do not support the concept of italic or underlined text (at least, not yet) - so those styles become combinations of the blink and high-intensity attributes which can be used to choose alternate fonts and this works well. These 4 styles were chosen to be compatible with GoldEd's "Style Codes", though GoldEd is actually very configurable in its support of these tags/codes and its possible we're not 100% compatible. For example, GoldEd (and SemPoint) both support the combining of tags/codes to created combinations of styled text - Synchronet does not (this is consistent with Mozilla/Thunderbird's "Structured Text"). Multiple words can be styled with a single set of tags, but the first and last word must be delimited by white-space (this is not consistent with Markdown). Multiple lines can be styled with a single set of tags, but not multiple paragraphs (this is consistent with Markdown). The rules I chose were to minimize false positives but maintain some interoperability with GoldEd and Thunderbird with a familiar/common tag syntax.