Ability to specify dependency targets to skip at the CLI

There are often times where I am developing a task at the end of a list of targets. During this temporary development I want to run the target frequently without running the targets it depends on.
Naturally I comment out the `.IsDependentOn` for the task under development. However I'd strongly prefer to be able to specify `-Target X -SkipTarget Y -SkipTarget Z` or something similar. I don't want to make any changes to the file on account of temporary development. This way I can commit as I make progress without forgetting to uncomment and recomment.

I'd also prefer not to build a hierarchy where `Release` depends on `Test` and `ReleaseWithoutTest` or introduce environment variables or any other kind of script boilerplate just for the sake of being able to temporarily skip a given target.

Start by tracing how the CLI parses repeated target options and how target dependencies are selected for execution. Define the behavior for multiple skip-target values, including their effect on dependencies, then add or update tests for command-line parsing and dependency execution. Done means a target can be run while named dependency targets are skipped without editing the build script.

Written by the indexing model from the issue text.