Preserve License Comments

gistfile1.js

uglify: {
      options: {
        mangle: {
          except: ['jQuery']
        },
        preserveComments: 'some',
        banner: '<%= banner %>',
        report: 'min'
      },
      my_targets: {
        files: {
        '<%= globalConfig.jsDest %>/base.min.js': ['<%= globalConfig.jsDest %>/base.js']
        }
      }
    }