Convert (most of) the test data files into genuine XML. A handful still

are not, due mainly to the lack of support for XML character entities
(e.g. & => & ).  This will make it easier to validate test files using
tools like xmllint, as well as edit and view them using XML tools.

tests/data/test78

@@ -1,3 +1,4 @@
+<testcase>
 <info>
 <keywords>
 HTTP
@@ -19,7 +20,7 @@ Connection: close
 Content-Type: text/html
 Funny-head: yesyes
 
-<foo>
+-foo-
 </data>
 <datacheck>
 HTTP/1.1 200 OK
@@ -63,3 +64,4 @@ If-Modified-Since: Sun, 12 Dec 1999 11:00:00 GMT
 
 </protocol>
 </verify>
+</testcase>