* controlfiles/artscomponents/linemixing/TestLineMixingAndZeeman_50_to_70_G:
Updated the slow test so that it no longer fails after arts-xml-data update.



git-svn-id: https://www.sat.ltu.se/svn/rt/arts/trunk@8818 aaf1aab0-4228-0410-ad68-8dceda47f409
* arts-2-1-854

* src/file.{cc,h} (find_file, find_xml_file):

In some cases the same file could be found through different paths
(absolute/relative/~). This led to a warning being issued even though
the two paths pointed to the same file. All filenames are now converted
to absolute paths to avoid this. Bug reported by Richard.

Sometimes the search order was wrong for filenames that needed an
extension to be appended to be found. find_xml_file would return a
match from a directory that is placed later in the search path than the
directory which contains the correct match.

Reverted change from 2-1-850: Ignoring the search path for filenames
starting with './' breaks things when running arts from a different
path than where the controlfile is located. Although using ./ to force
the file being read from the current directory would be 'more correct'
than what we do now, the problem is that '.' currently means 'the
directory where arts is called'. It would work correctly if '.' could
be expanded to 'the directory where the controlfile / include file is
located that contains the ReadXML statement for this file'. The cost of
implementing this logic in the parser doesn't justify the relatively
low benefits.

git-svn-id: https://www.sat.ltu.se/svn/rt/arts/trunk@8820 aaf1aab0-4228-0410-ad68-8dceda47f409