normalise pathPrefix in filesystem-adapter-local
add pathPrefix param to CM_File::listFIles()
Revert "add pathPrefix param to CM_File::listFIles()"

This reverts commit 79adb83d8a7ad95a68aaa04fc864720c16390a15.
Merge pull request #1346 from alexispeter/lsitfiles-pathprefix

Normalise pathprefix in CM_Filesystem_Adapter_Local::listFiles()