FTP code turned into state machine. Not completely yet, but a good start.

The tag 'before_ftp_statemachine' was set just before this commit in case
of future need.

tests/data/test190

@@ -15,7 +15,7 @@ ftp
 FTP download with strict timeout and slow CWD
  </name>
  <command>
-ftp://%HOSTIP:%FTPPORT/path/to/file/126 -m 3
+ftp://%HOSTIP:%FTPPORT/path/to/file/190 -m 3
 </command>
 <file name="log/ftpserver.cmd">
 DELAY CWD 15
@@ -24,6 +24,7 @@ DELAY CWD 15
 
 # Verify data after the test has been "shot"
 <verify>
+# 28 is CURLE_OPERATION_TIMEOUTED
 <errorcode>
 28
 </errorcode>