Is it possible to set tab size for different type of file? #112

Hi, there

Can we make setting to set different tab size for type of files, such as set tab_size: 2 for ruby file(.rb) and for tab_size: 4 for ruby template file(.html.erb)

I try to use "Setting-Syntax specific" to set different tab size for different type of file, but it's working.

Hope to add a setting for different type of file. Thanks.