Allow short or --verbose output

[aleh807]

Hey! My recent project has grown to the point that now dom_munger updates/inserts a lot of parts (100s) into html. With this being said a lot of unnecessary logs are written to output, like "Appended to body", which brings 0 value and frustrates when I need to see logs that were written before munger. My suggestion is to use grunt.verbose instead of grunt.log in the places where we insert/update/delete something. This will allow to use --verbose flag when running grunt tasks to see full output if needed.