Reorganize code, put some ZPermissionsPlugin methods behind interfaces to facilitate future refactoring.

--HG--
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/WorldPermission.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/QualifiedPermission.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/CommonCommands.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/command/CommonCommands.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/DirTypeCompleter.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/command/DirTypeCompleter.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/GroupCommands.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/command/GroupCommands.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/GroupTypeCompleter.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/command/GroupTypeCompleter.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/MetadataCommands.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/command/MetadataCommands.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/PlayerCommands.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/command/PlayerCommands.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/RootCommands.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/command/RootCommands.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/SubCommands.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/command/SubCommands.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/TrackTypeCompleter.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/command/TrackTypeCompleter.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/ZPermissionsPlayerListener.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/event/ZPermissionsPlayerListener.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/ZPermissionsRegionPlayerListener.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/event/ZPermissionsRegionPlayerListener.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/AvajeStorageStrategy.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/storage/AvajeStorageStrategy.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/MemoryStorageStrategy.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/storage/MemoryStorageStrategy.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/StorageStrategy.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/storage/StorageStrategy.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/ExpirationRefreshHandler.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/util/ExpirationRefreshHandler.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/ModelDumper.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/util/ModelDumper.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/RefreshTask.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/util/RefreshTask.java
rename : src/main/java/org/tyrannyofheaven/bukkit/zPermissions/Utils.java => src/main/java/org/tyrannyofheaven/bukkit/zPermissions/util/Utils.java