Merge pull request #5463 from benti/4.2

Fixed wrong @return type.
Fix an error in Collection->random()

Fix an error on random() if called on an empty collection. Returns null instead.
Merge pull request #5323 from GrahamCampbell/4.2-morph

[4.2] Corrected A Docblock
Write the compiled file to the storage directory.
Dockblock fix
Implement NullStore in Illuminate\Cache.
Working on some new structure things.
Work on app:name command.
Trim namespace slashes.
Fixing bugs in app:name command.
Work on generators.
Fix test.
Simplifying controller generation.
Working on generator code clean-up.
Change app name command autoload dump.
Fix a slight bug in action URL generation.
Change order of check.
Fix namespace slash.
Simplify remindres-controller command.
Import class.