fixed an issue of protocol changed during 302.
removed debug info.
added reschedule callback interface.
added frame work for ftp.
adding files ported from wget.

Not finished.
compiles now.
..
can log in to ftp now.
connect/auth/size/rest passed.
adding data connection, not finished.
..
usable...
...
enabled option to show metadta.
added function to hash tables: dump and parse.

this can be used to store all key/value pairs in metadata.
dumping hash_table to buffer, not completed yet!
Use hash table to record url/user/passwd/xxx.
removed debug logs.
select pipes to report progress, not finished.
ftp works with progress reported.