Improve error message for bad build targets

[sjakobi]

See #2382.

The error message "Could not find a component named warp" could be a lot better:

It could:

• point out the available targets (or refer to stack ide targets)
• detect that a target refers to a non-local package
• link to documentation

[v0d1ch]

Is this ticket still needed? When running:

stack build --file-watch --test --copy-bins --haddock wai-extra :warp warp:doctest 
  --exec 'echo Yay, it worked!'

I get:

- warp doesn't seem to be a local target. Run 'stack ide targets' for a list of available targets
- Unknown local package: warp

So it seems we have the information that warp is probably not a local target.

If we still need to implement this what should be the best error message here @mgsloan ?

[sjakobi]

@v0d1ch Thanks for the update!

I think that error message is good enough to close the issue. Feel free to re-open if you disagree of course!