v4.2.2

• Security: the regular expressions for strings and comments backtracked in
  exponential or quadratic time. A short document could cause a denial of
  service. The rules now match in linear time. See
  GHSA-v667-mm43-5q7r.
  (#195)
• Some documents parsed wrongly and now follow the spec: a="x\" and
  a='x\'y' raise TomlRB::ParseError, a=['C:\', 'D:\'] parses, and
  a='C:\' # ' gives "C:\\" and a comment. (#195)