Add support for multiple apps

It would be nice to unify brunch approach to building very complex apps, modularity etc.

• app/ should no longer be created by default. Instead, there should be a directory, that has the same name as <app>. E.g. forum for brunch new forum.
• Load paths for everything should start from paths.root instead of paths.app. There should be no special case for app/.
• assets/ and vendor/ directories of every app should have special meaning, like they have today. Of course, their presence should be absolutely optional.
• Changing of paths.assets / paths.vendor should be prohibited.
• paths.app should be deprecated, instead, apps or perhaps paths.apps should be added.
• Because it will be probably backwards-breaking, it would require version bump to 2.0.

Still not sure:

• What if user has many (10+) apps? Root directory will be very dirty. Maybe there should be an apps directory for this and other use cases (and no config param at all).
• Where should default skeletons contain app files? <app name>/app or <app name>?

Example of new structure

apps/
  forum/
    assets/
    controllers/
    models/
    views/
    vendor/
  admin/
    assets/
    controllers/
    models/
    views/
    vendor/
  chaplin/
    controllers/
    models/
    views/
config.coffee
node_modules
package.json
public/
README.md
vendor/ (optional)

[blaine]

Actually, just after posting my comment here, I’ve found a workaround.

What I’ve ended up doing is:

joinTo:
  'javascripts/app.js': /^app(\/|\\)(?!admin)/
  'javascripts/admin.js': /^app(\/|\\)(?=admin)/

which achieves the “multiple app” effect I was looking for. Hope that helps others.

[paulmillr]

So I think brunch 1.4 apps fit greatly for multiple app env already, as per latest comments.