Translatable objects

In order to support fully internationalizable applications, objects should also be translatable.

Right now you can add a custom field, "lang" for example, and request an object using it as a key, but this has several disadvantages:

• now you have more than an object for the same information
• you can't reuse untranslatable fields
• it's hard to maintain language-independent fields to the same value
• you can't automatically return the correct language from a search

Proposal:

• Like document content, for which we have a language property, all datatype tables should have language fields
• Each class property should have a "translatable" option
• Translating a document should also translate the translatable fields
• Each Property should store and retrieve its value in/from the proper field, according to the translatable option and the current language