Support Metadata On All DSpaceObjects

This pull request adds metadata to all DSpace Objects. The metadata is stored in the already existing metadatavalue table.

Community/Collection/Bundle/Bitstream "metadata" columns have been moved from their database tables to the metadata registry. For example the "name" of these objects has been moved to a dc.title metadata field.

The EPerson class has received a separate "schema" in order to support the eperson metadata, this schema will be created on ant fresh_install/update.