astropy.io.votable: no write_to method

According to the documentation at
http://docs.astropy.org/en/latest/io/votable/index.html#converting-to-from-an-astropy-table-table
there should be a method to transform astropy tables into VO table, called `write_to`. However, this methods seems not to exist.
I am not sure if that is a problem with the documentation or with the implementation.
```
In [7]: import astropy.io.votable

In [8]: astropy.io.votable.
astropy.io.votable.connect
astropy.io.votable.converters
astropy.io.votable.exceptions
astropy.io.votable.from_table
astropy.io.votable.IOWarning
astropy.io.votable.is_votable
astropy.io.votable.parse
astropy.io.votable.parse_single_table
astropy.io.votable.table
astropy.io.votable.tablewriter
astropy.io.votable.tree
astropy.io.votable.ucd
astropy.io.votable.UnimplementedWarning
astropy.io.votable.util
astropy.io.votable.validate
astropy.io.votable.VOTableChangeWarning
astropy.io.votable.VOTableSpecError
astropy.io.votable.VOTableSpecWarning
astropy.io.votable.VOWarning
astropy.io.votable.xmlutil
```