Improve CLI interactions and caching URL

[elcritch]

Some more work on CLI and some related changes for speed.

• suppress redundant info like installed package foo on default outputs
• adds --info flag to print the extra info without a full verbose (MediumPriority)
• modifies nimble deps to print out only direct dependencies and versions
  • this seems more like what people expect when running nimble deps
• nimble deps --tree prints out the full dedendency tree
• info about url based deps are cached in a packages_nimblecached.json PkgList

I did some simple timing on one of my projects and get:

# Before cachine URL checks
figuro> nimble deps  2.03s user 0.55s system 26% cpu 9.877 total
# After caching URL checks
figuro> nimble deps  1.38s user 0.24s system 83% cpu 1.931 total

[elcritch]

I'd also like to add a nimble deps --update and maybe a nimble deps --install options. Ideally a nimble deps --update would be a great way to do network related work but upon explicit request. This is how Elixir's mix package manager works and it's great to use.

@Araq what would you think about adding that?

[Araq]

@Araq what would you think about adding that?

Fine with me but the naming could be better.