docs for ProjectableFilterableTable.scan()'s filter argument

[Alexey Roytman]

The documentation section for ProjectableFilterableTable.scan() is 
somewhat self-contradicting:
   ...
   * If the table can implement a particular filter, it should remove that
   * filter from the list.
   * If it cannot implement a filter, it should leave it in the list.
   ...
   * @param filters Mutable list of filters. The method should remove 
from the
   *                list any filters that it cannot apply.
   ...
The contradiction comes from the method description and the @param for 
the 'filters' argument.

- Alexey.