Aliases on column names

[dsavina]

In some cases, it could be practical to be able to alias columns names. For example, I've seen a project where the client required for the database to be in French. It would be very cool if the PHP code generated by TDBM could despite that be in English (names of the getters/setters and json serialization), using a per-column english translation as an alias.

I see that TDBM tries to match @defaultSort desc/asc in the columns comments to define a default sort column on a table (by the way, wouldn't it be preferable to look for order in the comment of the table itself? If several columns have this annotation, only the last one will be taken into account) ; similarly, we could specify an annotation @alias <alias>.

More generally, this little piece of code using columns comments to define a default sort column broke my mind: so many cool things to do using annotations in the comments of the database.

[moufmouf]

Linking this to #53 as both are heavily related.