wget: more thorough sanitization of other side's data

wget: more thorough sanitization of other side's data

function                                             old     new   delta
get_sanitized_hdr                                      -     156    +156
fgets_trim_sanitize                                    -     128    +128
ftpcmd                                               129     133      +4
parse_url                                            461     454      -7
sanitize_string                                       14       -     -14
wget_main                                           2431    2381     -50
fgets_and_trim                                       119       -    -119
gethdr                                               163       -    -163
------------------------------------------------------------------------------
(add/remove: 2/3 grow/shrink: 1/2 up/down: 288/-353)          Total: -65 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>