Added variables for more core modules and some more variable types.
Updating from http://github.com/josereyero/variable
29c6d94 Added locale/language variables. Added multiple_node_type type.
c3ae92a Fixed issue with mail variables
f5478bb Added translation for some string, variable type select_country, other improvements
6074831 Added forum variables, taxonomy variable type, and generic array variables
94cb462 Added core variables for system, menu
5a6ab15 Added generic form for variable selection, used by i18n