Verbose logs the location of a task definition.

[jdhuntington]

Overview

In large monorepos with many levels of indirection between a task being defined and being invoked, it can be difficult to trace back to where a problem exists.

This change adds functionality that will emit a truncated stack trace when just is run with --verbose.

Also causes the logger to run in verbose mode when JUST_VERBOSE is defined as an environment variable, as just is often run behind levels of indirection making command line arguments more difficult to pass.

[kenotron]

probably should use this: https://www.npmjs.com/package/callsite

something like this: https://stackoverflow.com/questions/18144921/how-do-i-get-the-dirname-of-the-calling-method-when-it-is-in-a-different-file-in