Bugfix: take modifications of cache_path in event front.start into account

Fix a regression introduce in be9211f001b5713bb6512bfab6b05ab242103dc6

The modification of $cache_path in the event front.start was no longer used.
It was working in chiba.1, and no longer working in chiba.2.
Merge pull request #66 from jay3/patch-9

Bugfix: take modifications of cache_path in event front.start into account