tests: Added test for POP3 DELE command

tests/data/test858

@@ -0,0 +1,40 @@
+<testcase>
+<info>
+<keywords>
+POP3
+DELE
+CUSTOMREQUEST
+</keywords>
+</info>
+
+#
+# Server-side
+<reply>
+</reply>
+
+#
+# Client-side
+<client>
+<server>
+pop3
+</server>
+ <name>
+POP3 DELE message
+ </name>
+ <command>
+pop3://%HOSTIP:%POP3PORT/858 -u user:secret -X DELE -I
+</command>
+</client>
+
+#
+# Verify data after the test has been "shot"
+<verify>
+<protocol>
+CAPA
+USER user
+PASS secret
+DELE 858
+QUIT
+</protocol>
+</verify>
+</testcase>