filecache: refactor path join logic to a function
New users of filecache use different names for the function used to compute
the runtime path of the cached file.
Users should subclass filecache and provide their own version of this
function to call the appropriate join function on 'obj' (an instance
of the class that its member function was decorated).
default = 'changelog'
mimetype = 'text/xml; charset={encoding}'
header = header.tmpl
changelog = changelog.tmpl
changelogentry = changelogentry.tmpl
filelog = filelog.tmpl
filelogentry = filelogentry.tmpl
tags = tags.tmpl
tagentry = tagentry.tmpl
bookmarks = bookmarks.tmpl
bookmarkentry = bookmarkentry.tmpl
error = error.tmpl