Buffer styled printing

When printing directly to stdout, there is a non-negligible overhead
compared to simply printing to an IOBuffer. Testing indicates 3
allocations per print argument, and benchmarks reveal a ~2x increase in
allocations overall and much as a 10x increase in execution time.

Thus, it seems worthwhile to use a temporary buffer in all cases.

base/strings/io.jl

@@ -1004,19 +1004,22 @@ end
 function _ansi_writer(io::IO, s::Union{<:StyledString, SubString{<:StyledString}},
  string_writer::Function)
  if get(io, :color, false)::Bool
+ buf = IOBuffer() # Avoid the overhead in repeatadly printing to `stdout`
+ lastface::Face = FACES.current[][:default]
  for (str, styles) in eachstyle(s)
  face = getface(styles)
  link = let idx=findfirst(==(:link) ∘ first, styles)
  if !isnothing(idx)
  string(last(styles[idx]))::String
  end end
- !isnothing(link) && write(io, "\e]8;;", link, "\e\\")
- termstyle(io, face, lastface)
- string_writer(io, str)
- !isnothing(link) && write(io, "\e]8;;\e\\")
+ !isnothing(link) && write(buf, "\e]8;;", link, "\e\\")
+ termstyle(buf, face, lastface)
+ string_writer(buf, str)
+ !isnothing(link) && write(buf, "\e]8;;\e\\")
  lastface = face
  end
- termstyle(io, getface(), lastface)
+ termstyle(buf, getface(), lastface)
+ write(io, take!(buf))
  elseif s isa StyledString
  string_writer(io, s.string)
  elseif s isa SubString