Parameter to limit output by page language

[stanolacko]

Feature summary (what you would like to be able to do and where):
I want to have parameter language to limit output by requested language.

Use case(s) (list the steps that you performed to discover that problem, and describe the actual underlying problem which you want to solve. Do not describe only a solution):
Wiki using Translate extentions.

Benefits (why should this be implemented?):
Success on multilanguage wikis.