adoc-style

#Bold with single asterisks.
s/(\*\*)([a-z ,.]+)(\*\*)/*\2*/g

#Use blocks for admonistions.
s/(^NOTE|^TIP|^WARNING|^IMPORTANT|^CAUTION)(:)([ ]?)([A-Za-z .?:!'"\*]+)/\[\1\]\n====\n\4\n====\n/g