Option to display file contents in a particular color

This is an Enhancement suggestion, but I don't know how to add the tag..

It would be great if we could set a color for the displayed file, so it doesn't get lost in the console amongst the other stuff.

I noticed you are using "process.stdout.write" to print out the contents of files.

So perhaps we could do something like:

``` js
var color = require('ansi-color').set;
process.stdout.write(color("file contents in string format", some_ansi_color_string_var));
```

and then use gulp-cat like

``` js
gulp.task('taskname', function() {
gulp.src('./README.md')
.pipe(cat( { color: "blue" } ));
});
```

Trace the output path that currently calls process.stdout.write and inspect how gulp-cat options are parsed. Use the proposed gulp.task configuration as the expected interface, then verify that file contents can be emitted in the selected color while the default output remains unchanged.

Written by the indexing model from the issue text.