added more constructors for v4
changed String to AbstractString for 0.4
streamlining and suggestions per discussion
IPv4(Array) -> Array(IPv4)
switch to map() to preserve concrete type
commenting out IPv4(Vector) -> Vector(IPv4) until a decision can be made
explain resize! behavior; fixes #9313
turn on colored output for Pkg.test()
Make `Pkg.build` error message clearer.
add graphemes(s) function to iterate over graphemes (represented by substrings) of a string s
Merge pull request #9373 from davidssmith/resize

explain resize! behavior; fixes #9313
Update networking-and-streams.rst

`read(stream, array)` is deprecated in favor of read!()
Merge pull request #9158 from lucasb-eyer/pkgbuild-error

Make `Pkg.build` error message clearer.
fix #7395, and copy just the useful parts of CONTEXT in jl_throw_in_ctx, before rec_backtrace_ctx destroys the recorded stack pointer
Merge pull request #9383 from nsaphra/patch-1

Update networking-and-streams.rst
fix 32 bit oops from ed5a8fcb93
REPL: passthru ctrl-arrow keys
Turn on colored output for Pkg.test() if Base.have_color is true
Merge pull request #9388 from JuliaLang/rf/repl-ctrl-arrow

REPL: passthru ctrl-arrow keys
Merge pull request #9374 from JuliaLang/jcb/testcolor

Turn on colored output for Pkg.test()