Colorized dialyzer output

[Licenser]

Some nicer dialyzer messages, making larger ones readable.

what was

https://monosnap.com/file/nARGsi1CvHoliGTukbRgdUFEvAe7cK

is now

https://monosnap.com/file/HgKtFqC90RqoKU5Du4wN5GYPnUd50w

[ferd]

Heads up that a lot of colors can already be handled by erlware_commons (we use them in rebar3) and the deps there can be reused.

[andrzejsliwa]

great work @Licenser

[Licenser]

Reached a pretty good place, all messages are colored, some I haven't seen in the wild are naively colored and perhaps can be improved later on. General color rules are:

Readable text: Bold
Bad argument/element: red
Good/expected: green
position number: blue

If something fails to output (i.e. there is an error it will fall back to the old output form).

@ferd I Looked at the commons stuff but the code does not provide the kind of capabilities I need here, or the functions in question are not exported.

[Licenser]

Note: the failed test is a issue with fetching dependencies on travis.

[tsloughter]

+1

@ferd merge if you are good with it. We have a lot built up as well and should cut beta-3. But with a proper version tag this time.

[ferd]

The color scheme outputting white really messes up with light color schemes:

The bold color should be reset to the shell default, and not just assume white is the right thing to do I guess. Can't merge for now as this makes output unreadable.

[Licenser]

@ferd thanks for the light terminal catch :) I'd have missed that, fixed it now it's "bold" not "bold white" and works on both light and dark backgrounds:

[ferd]

Merging when tests pass.

[ferd]

On second look, your screenshot seems to show a bug: ~{~<Default>,'default'>,...

[ferd]

It appears that the line [~{~<Default,'default'>, ~<Desc,'desc'>, ~<Scope,'scope'>}~ | _] is how Dialyzer represents map syntax. Given Dialyzer will sooner or later properly support it, we'll keep it as is right now -- it's also compatible with current stuff and old stuff at once. Merging.