Leak fix.
Remove unused global reference.
We now log in verbose when purging old connections

It shouldn't happen anyway. Also refactored the function a bit to make
it more readable, it now has only one exit point: its end.
In case of error from PreprocessRequestPath() errno is not always set.
access_rules: trailing slashdot signifies a directory, just like trailing slash. Redmine #5775.
Rename dest_file_latest to destination_file in acceptance tests where latest protocol is all we test.
Remove the protocol latest parameter in body copy from, for acceptance tests that apply only to the latest protocol.
Add acceptance tests for recursively admitted directories in access_rules.

Test access_rules for inexistent directories, with recursive access
being signified as such by either trailing slash or trailing
slashdot. Also test denial of specific files within the recursively
admitted directories.
The reference to the list must not be NULL.
Merge pull request #1709 from jimis/minor

Trailing slashdot in access rules, redmine #5775