Moved API to standalone project.
Need JUnit test depend.
srcurl -> source.
Proper depends.
Provide some basic interaction with pacman.
SPackageManager -> PackageManager.
No longer use srcdir and bindir.
Include jsr305 for Guava's annotations.

scalac 2.11.1 in theory won't crash without this, but I don't want to see the
warnings either. Oh Java, why can't you just add a Nullable annotation and save
everyone the damned trouble?
Use a source depend for Reactual.
Nix debug logging.
Nix listPackages for now.
Merged API project back in under api/.