Fixed [web] allow_archive for comma separated parameters by using ui.configlist.
Changed tests/test-archive to use allow_archive instead of the deprecated
allowzip, allowgz and allowbz2.
Added ui.configlist method to get comma/space separated lists of strings.
For example:
users = alice, bob
colors = red green blue
Fix ui.expandpath problem and broken test introduced by
4a2a4d988ead.