internal: Fix caches being orphaned from their directory. After clearing caches, the instances in memory don't have a file-system directory anymore. This means that either caching data would crash the app, or, in the case of baking a site, would make the workers create the directory but collide randomly while doing so at the same time.

colorama==0.3.3
compressinja==0.0.2
Jinja2==2.7.3
Markdown==2.6.2
MarkupSafe==0.23
Pygments==2.0.2
pystache==0.5.4
python-dateutil==2.4.2
PyYAML==3.11
repoze.lru==0.6
smartypants==1.8.6
strict-rfc3339==0.5
textile==2.2.2
Werkzeug==0.10.4