test2017 to test2022: more metalink tests

With this commit, checks done in previous test2017 are now done in test2018.

Whole range test2017 to test2022 DISABLED until configure is capable of
requiring a new-enough metalink library.

Don't try these without mentioned check in place!

tests/data/test2017

@@ -35,7 +35,7 @@ file
 Metalink
 </features>
  <name>
-Metalink local XML file, attempt questionable file name
+Metalink local XML file, attempt UNIX home path traversal
  </name>
 <command option="no-output,no-include">
 --metalink file://%PWD/log/test2017.metalink
@@ -45,7 +45,7 @@ Metalink local XML file, attempt questionable file name
 <?xml version="1.0" encoding="utf-8"?>
 <metalink version="3.0" xmlns="http://www.metalinker.org/">
  <files>
-  <file name="log/.download2017">
+  <file name="~/download2017">
    <verification>
     <hash type="sha256">c7d03debe90ca29492203ea921d76941fa98640cf3b744f2a16c9b58465eab82</hash>
    </verification>
@@ -57,7 +57,7 @@ Metalink local XML file, attempt questionable file name
 </metalink>
 </file>
 <postcheck>
-perl %SRCDIR/libtest/notexists.pl log/2017 log/name2017 log/.download2017
+perl %SRCDIR/libtest/notexists.pl log/2017 log/name2017
 </postcheck>
 </client>
 
@@ -72,7 +72,7 @@ Metalink: parsing (file://%PWD/log/test2017.metalink) WARNING (missing or invali
 Metalink: parsing (file://%PWD/log/test2017.metalink) FAILED
 </file2>
 <stripfile2>
-$_ = '' if ($_ !~ /^Metalink: /)
+$_ = '' if (($_ !~ /^Metalink: /) && ($_ !~ /error/i) && ($_ !~ /warn/i))
 </stripfile2>
 </verify>
 </testcase>