Bug Report or Feature Request (mark with an x)

- [ ] bug report -> please search issues before submitting
- [x] feature request

Versions.

@angular/cli: 1.3.0-beta.1
node: 8.2.0
os: darwin x64

Repro steps.

ng build/serve command do support --preserve-symlinks option, while ng test does not:

$ng build --help | grep sym
  --preserve-symlinks (Boolean) (Default: true) Do not use the real path when resolving modules. 
$ng test --help | grep sym
# empty
$ ng test --preserve-symlinks
The option '--preserve-symlinks' is not registered with the test command. Run `ng test --help` for a list of supported options.

Desired functionality.

I think it'd make sense to support symlinked modules in the test command too.
The test command does not include common build options, while serve does:
https://github.com/angular/angular-cli/blob/master/packages/@angular/cli/commands/serve.ts#L33
Not sure if that's intentional for some reason or by mistake.