Set up multilingual environment for using LANGUAGE-NAME.
This sets the coding system priority and the default input method
and sometimes other things. LANGUAGE-NAME should be a string
which is the name of a language environment. For example, "Latin-1"
specifies the character set for the major languages of Western Europe.
If there is a prior value for `current-language-environment', this
runs the hook `exit-language-environment-hook'. After setting up
the new language environment, it runs `set-language-environment-hook'.