Add lerna tasks

[A77AY]

I would like to run nested tasks of the lerna monorepository:

my-lerna-repo/
  package.json
  packages/
    package-1/
      package.json
    package-2/
      package.json

Possible solutions:

• get paths from lerna.json and yarn workspaces from package.json

• usage lerna utils for get paths (such as lerna-get-packages), but soon will be released lerna 3 and utils changed