docker inspect: add support for swarm configs

[thaJeztah]

The docker inspect command did not inspect configs. This patch adds support for it, and while at it, also sorts the list of objects in runInspect.

Before this patch:

docker config create myconfig ./codecov.yml
danpeyh8qzb30vgdj9fr665l1

docker inspect --format='{{.ID}}' myconfig
[]
Error: No such object: myconfig

docker inspect --format='{{.ID}}' --type=config myconfig
"config" is not a valid value for --type

With this patch:

docker inspect --format='{{.ID}}' myconfig
danpeyh8qzb30vgdj9fr665l1

docker inspect --format='{{.ID}}' --type=config myconfig
danpeyh8qzb30vgdj9fr665l1

- What I did

- How I did it

- How to verify it

- Description for the changelog

docker inspect now also allows inspecting swarm configs

- A picture of a cute animal (not mandatory but encouraged)

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 10 lines in your changes missing coverage. Please review.

Project coverage is 59.60%. Comparing base (61baf2a) to head (e9ae9f7).
Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5573      +/-   ##
==========================================
+ Coverage   59.21%   59.60%   +0.38%     
==========================================
  Files         342      345       +3     
  Lines       29083    29103      +20     
==========================================
+ Hits        17222    17346     +124     
+ Misses      10889    10788     -101     
+ Partials      972      969       -3