Unfortunately, this is not something immediately available, but it looks like this will be in the next version of Visual Studio. The bundling features I've read about will automatically bundle a specified selection of files into a single HTTP request.
The astute among you will probably already be aware that there's already
SharePoint) in the form of the Script Manager control which you can use to
create what's called a Composite Script and something we've exploited in our
SharePoint 2010 publishing projects. As the name implies, it only manages
scripts so what it lacks is any kind of support for CSS.
The next version appears to not only enhance the current "bundling"
functionality but also extend it for use with CSS files (and there may even be
some possibility of extending this to other file types if the class model will
allow). This means that multiple CSS files can then be "bundled" in the same
way, thereby minimising the number of HTTP requests. Not only can we do that,
but we will also be able to minify the bundled files.
the process of removing unnecessary characters from a file, like spaces,
carriage-returns, possibly semi-colons, comments etc. It can be used to reduce
files size considerably, and if the file size is small, the HTTP request will be
quicker to return to the browser. There are already sites out there that can be
used to do this, but to have it within Visual Studio will be very useful. How
much this will be integrated with SharePoint I don't know. As SharePoint is
based on a specific version of the .Net framework
this functionality may not make it into the next version - we'll have to wait
The main drive behind these changes appear to come from the necessity to
provide a better web UX for mobile devices where low and slow bandwidth can
inhibit use of a website. We'll just have to wait and see how and if it
surfaces in the next version of SharePoint.
If you want to know more, check out Scott Guthrie's blog post: http://weblogs.asp.net/scottgu/archive/2011/11/27/new-bundling-and-minification-support-asp-net-4-5-series.aspx