Add PSR-4 class loader. (tests needed)
PSR-4 class loader: Add getters for PSR-4 prefixes. Rename PSR-0 related attributes by appending *Psr0. Add more comments.
PSR-4 loader: Fix comments: PSR-0 related methods should have comments refering to PSR-0 and prefixes. PSR-4 related methods should have comments refering to PSR-4 and namespaces.
Further improve comments.
PSR-4 ClassLoader: Bug fix: PEAR-like path needs ".php" appended.
Add unit tests for ClassLoader, covering PSR-0 and PSR-4.
AutoloadGenerator to support PSR-4. Tests included.
Travis CI should use bin/composer and not system-wide Composer.
run system-wide composer install and THEN run bin/composer install
Fix error on check exclude from download composer.json
Add psr-4 stuff in a few more places.
Validation to make the combination of target-dir with psr-4 illegal.
Fixed minor typo on 'require' property
Add information on how to run scripts manually
Removed sneaky typo
Docs: Added Note about tags vs. version constraint

I made this mistake myself a few days ago, so I think it will be useful to note that here.
SelfUpdateCommand: initial groundwork for --rollback
SelfUpdateCommand: only use 1 rollback snapshot at a time
SelfUpdateCommand: do not delete old snapshots, allow user to clean them
SelfUpdateCommand: removed unneeded return