Support for selecting Module when generating Component/Directive etc.

[probert94]

Since Angular-CLI beta 25, the "generate" command lets you specify a module (see angular/angular-cli#3811)
The generate Wizards could support this to (using a Combobox with available modules?).
The nearest module could be selected by default.

[probert94]

I just tested how this works and it seems like you must specify the path to the module file.
For example:
ng generate directive test --module ../app.module.ts

This allowes you to create a file in any directory and instead of declaring it in the nearest module, you can declare it in any module.

I have tested following cases:

• Specify a non-existing file -> Command fails, no files generated/changed
• Specify a file without @NgModule annotation -> Files are generated, but not added to any module
• Specify a file with more then one @NgModule annotation -> Files generated and declaration added to last @NgModule in specified file

@angelozerr I guess this feature won't be needed verry often, as you usually want declarations to go into the nearest @NgModule.
But if we want to support this, a basic support with a file-chooser could be implemented pretty fast and would be enough for now.
Later we could extend it to show only files, which contain at least 1 @NgModule-annotation.

[angelozerr]

To be honnest with you, I don't know @NgModule, so I trust you! Any PR are welcome, thanks!