Move cache directories to the data folder

Hi,

While working on the last patches I did a lot of test pushes to openshift. During that I noticed that due to the repo being overwritten all caches and especially the feed-icons folder got nuked every time.
What I did for my local branch was to move these directories to the data directory with the exception of the feed-icons dir. Since it is actually used to serve files instead of moving it I moved it to the data dir and created a symbolic link.

This patch is actually working quite well, but maybe there is a better way to implement it.