Add dep_cowboy_commit 2.8.0 and a note in the user guide
dependencies section that the versions in the package index
are not always up to date.

https://concuerror.com/

The query-deps, query-doc-deps, query-rel-deps, query-test-deps
and query-shell-deps targets go through dependencies and print
some information about them:

  $ make query-deps
  ...
  cowboy: cowlib git https://github.com/ninenines/cowlib 2.7.3
  cowboy: ranch git https://github.com/ninenines/ranch 1.7.1

  $ make query-deps QUERY="name repo version absolute_path"
  ...
  cowboy: cowlib https://github.com/ninenines/cowlib 2.7.3 /path/to/deps/cowlib
  cowboy: ranch https://github.com/ninenines/ranch 1.7.1 /path/to/deps/ranch

The query-deps target is recursive; the others aren't. This
mirrors the behavior when fetching and building dependencies.

The full list of options is:

  QUERY="fetch_method name repo version extra absolute_path"

When an option has no corresponding value, "-" will be printed.
For example most fetch methods do not have extra information to
print. When there is extra information, the value will be prefixed
with a descriptive name. For example: package-name=uuid_erl

This commit also introduces changes to deps handling: some of
the functions for querying will now be used directly. In the
future the goal is to remove the old dep_name, dep_commit, etc.
functions and replace their usage with the new query functions.

Custom fetch methods should implement query functions in order
to have information about the relevant dependencies printed
properly.

Properly fixes partisan.

There are issues with -j in 4.1 and earlier.