EDB.Serializable: added interface
examples/serial: now outputting the Base64-encoded serial
EDB.Serializable: removed useless method
Merge branch 'master' into embedded_database
EDB.Serializable: added functionality to exclude properties

When you define a method called serializable_exclude_properties in
an Object which implements the Serializable interface, you can return
a string[] of properties that are neither used for generating the
class-identifier nor for serialization itself.

This means that their value is simply ignored and does not influence
the serialization process at all.
EDB.Serializable: added optional properties

When you define the method serializable_optional_properties in your
object which implements Serializable, you can return a string[] which
is not used during generation of the class-identifier.

This can be used for example to define new properties on an object and
maintain backwards-compatibility.
EDB.Serializable: reworked interface and changed binary-format of serials
Serializable: changed namespace