Improve presentation of published port ranges

[thaJeztah]

fixes#178

Port mappings in docker service ls are quite verbose, and occupy a lot of
space when ranges of ports are published.

This patch improves the output by reconstructing ranges of ports.

Given the following service;

$ docker service create \
-p 60-61:60-61 \
-p 62:61 \
-p 80:80 \
-p 81:80 \
-p 90-95:90-95 \
-p 90-92:90-92/udp \
-p 93-96:93-96/udp \
--name foo \
nginx:alpine

Before this patch is applied:

$ docker service ls
ID NAME MODE REPLICAS IMAGE PORTS
u1kwguv841qg foo replicated 1/1 nginx:alpine *:60->60/tcp,*:61->61/tcp,*:62->61/tcp,*:80->80/tcp,*:81->80/tcp,*:90->90/tcp,*:91->91/tcp,*:92->92/tcp,*:93->93/tcp,*:94->94/tcp,*:95->95/tcp,*:90->90/udp,*:91->91/udp,*:92->92/udp,*:93->93/udp,*:94->94/udp,*:95->95/udp,*:96->96/udp

After this patch is applied:

$ docker service ls
ID NAME MODE REPLICAS IMAGE PORTS
u1kwguv841qg foo replicated 1/1 nginx:alpine *:60-62->60-61/tcp,*:80-81->80/tcp,*:90-95->90-95/tcp,*:90-96->90-96/udp

Additional enhancements can still be made, and marked as TODO in this change;

• combine non-consecutive ports mapped to a single port (80->80, 81->80,
  84->80, 86->80, 87->80); to be printed as *:80-81,84,86-87->80.
• combine tcp and udp mappings if their port-mapping is the same;
  print *:80-81->80-81/tcp+udp instead of *:80-81->80-81/tcp, *:80-81->80-81/udp

- Description for the changelog

* Improve presentation of published ports by combining port-ranges [docker/cli#581](https://github.com/docker/cli/pull/581)

[thaJeztah]

ping @dnephin@vdemeester@jefflill PTAL

While working on this, I noticed that various commands include the formatted values when using --format '{{ json . }}'. I think we should look at that, and always print the raw values when printing JSON (not sure there's a way to do that on a "global" level, or if that has to be fixed for each command separately.

[codecov-io]

Codecov Report

Merging #581 into master will increase coverage by 0.14%.
The diff coverage is 100%.

@@ Coverage Diff @@## master #581 +/- ##
==========================================
+ Coverage 49.37% 49.52% +0.14% 
==========================================
Files 208 208 Lines 17178 17225 +47 ==========================================
+ Hits 8482 8530 +48 + Misses 8263 8262 -1 
Partials 433 433

[thaJeztah]

ping @dnephin@vdemeester 🤗

[dnephin]

LGTM

[vdemeester]

LGTM 🎉