Add links to documentation for all commands

[J0]

Fix #1729 . It seems that there isn't any documentation for dvc daemon and dvc pkg so I am omitting it for now.

[J0]

I have added documentation links to all the commands that I could find through dvc --help. Do let me know if there are any edits required. I'm not too sure where the help message fordvc status is though( I wasn't able to find it in dvc/dvc/command/status.py. Would be great if someone could point me in the right direction-- if not then I'll do a search for it tomorrow

[shcheklein]

This is great, @J0 ! Thanks. I suggest I add a dvc shortener for these links - something like help.dvc.org/commit -> dvc.org/doc/command-reference/commit. The main goal is to have a level of indirection we can control on the dvc.org website level. It's hard to always keep doc/* links up to date and I think it's not the best idea to depend on this. Give a bit of time to setup this redirect. What do you think? :)

[shcheklein]

@J0 man.dvc.org is alive. Try this: https://man.dvc.org/metrics or https://man.dvc.org/metrics-show

[shcheklein]

@J0 take a look at /dvc/command/data_sync.py for status command.

[shcheklein]

@J0 also, let's add help messages for subcommands as well - for example - https://man.dvc.org/metrics-show for dvc metrics show.

[shcheklein]

Great stuff!

See my comments to fix small things.

[dmpetrov]

It might be better to squash 32 commits into 1-10. Otherwise it might break our beautiful contributors-graph by creating a spike and changing the graph scale :)

$ git rebase -i HEAD~30
# follow instructions
$ git push -f

See: https://github.com/todotxt/todo.txt-android/wiki/Squash-All-Commits-Related-to-a-Single-Issue-into-a-Single-Commit

[shcheklein]

@dmpetrov there is a button for that. @efiop will do Squash and merge when PR is ready. No need to redo the history in the PR itself.

[J0]

Hey @shcheklein sounds good to me -- I'll get to it in about 10 minutes :)

[shcheklein]

@J0 no rush, thanks! I think we need to keep https:// prefix. There are some terminals that can make them clickable automatically. I'm not sure about man.dvc.org without the prefix. I would double check that.

[shcheklein]

saying that, it looks like Mac OS terminal can recognize the shorter version - man.dvc.org/metrics ... what about other environments - @efiop @MrOutis @pared ?

[efiop]

Thank you! 🎉 A minor formatting issue down below.

[efiop]

Let's reformat all of these this way:

    ADD_HELP = (
        "Add files/directories to dvc. \n"
        "documentation: https://man.dvc.org/add"
    )

so it is unified everywhere and we don't mix \ into all of these.

[J0]

Ok done

[efiop]

Thank you! 🎉