Feature request: Per file auto minify settings

[swashata]

Hello,

First of all thank you for this lovely plugin. It works really good and saves really a lot of time. I would like to request you of a feature that I think would come really handy.

Right now we've an option to auto minify all opened file. It would be really useful if we can somehow have an option on per file basis. Something like this:

1. We put some special string like /* sublime_auto_minify: true */ at the top of the file.
2. The minify checks for the line on opened files.
3. If present, then only it saves a minified file.