Remove trailing whitespace

I recently set my editor to remove trailing whitespaces, because it's frowned upon by most style guides. Some IDEs or formatters remove white space, and others ignore them... but I don't know of any that introduce trailing whitespace. So preemptively removing trailing whitespace avoids noisy diffs later.

I also tried out the [maven java formatter](http://maven-java-formatter-plugin.googlecode.com/svn/site/0.4/usage.html), but it made more substantial changes that might conflict with IDE settings. It might still be a good idea if there's a standard jclouds formatter configuration it can use.

Also, I only made these changes on the rackspace folder. If you want to update the rest, I used this command on OSX:
`find . -name \*.java | xargs -L1 sed -i "" 's/[ ]*$//'`