refactor package structure

...urce/java/ch/systemsx/cisd/bds/AbstractDataStructure.java

bds/source/java/ch/systemsx/cisd/bds/Container.java

...ource/java/ch/systemsx/cisd/bds/DataStructureFactory.java

bds/source/java/ch/systemsx/cisd/bds/DataStructureV1_0.java

...ource/java/ch/systemsx/cisd/bds/ExperimentIdentifier.java

bds/source/java/ch/systemsx/cisd/bds/IDataStructureV1_0.java

bds/source/java/ch/systemsx/cisd/bds/ProcessingType.java

bds/source/java/ch/systemsx/cisd/bds/Utilities.java

bds/source/java/ch/systemsx/cisd/bds/Version.java

bds/source/java/ch/systemsx/cisd/bds/storage/IDirectory.java

bds/source/java/ch/systemsx/cisd/bds/storage/IFile.java

bds/source/java/ch/systemsx/cisd/bds/storage/ILink.java

bds/source/java/ch/systemsx/cisd/bds/storage/INode.java

bds/source/java/ch/systemsx/cisd/bds/storage/IStorage.java

...ch/systemsx/cisd/bds/storage/filesystem/AbstractNode.java

...va/ch/systemsx/cisd/bds/storage/filesystem/Directory.java

.../ch/systemsx/cisd/bds/storage/filesystem/FileStorage.java

...ce/java/ch/systemsx/cisd/bds/storage/filesystem/Link.java

.../ch/systemsx/cisd/bds/storage/filesystem/NodeFactory.java

...a/ch/systemsx/cisd/bds/storage/filesystem/StringFile.java