added document captions support

Author: V V

interface.c

@@ -1737,10 +1737,10 @@ struct command commands[MAX_COMMANDS_SIZE] = {
   {"safe_quit", {ca_none}, do_safe_quit, "safe_quit\tWaits for all queries to end, then quits", NULL},
   {"search", {ca_peer | ca_optional, ca_number | ca_optional, ca_number | ca_optional, ca_number | ca_optional, ca_number | ca_optional, ca_string_end}, do_search, "search [peer] [limit] [from] [to] [offset] pattern\tSearch for pattern in messages from date from to date to (unixtime) in messages with peer (if peer not present, in all messages)", NULL},
   //{"secret_chat_rekey", { ca_secret_chat, ca_none}, do_secret_chat_rekey, "generate new key for active secret chat", NULL},
-  {"send_audio", {ca_peer, ca_file_name, ca_none}, do_send_audio, "send_audio <peer> <file>\tSends audio to peer", NULL},
+  {"send_audio", {ca_peer, ca_file_name, ca_string_end | ca_optional, ca_none}, do_send_audio, "send_audio <peer> <file>\tSends audio to peer", NULL},
   {"send_contact", {ca_peer, ca_string, ca_string, ca_string, ca_none}, do_send_contact, "send_contact <peer> <phone> <first-name> <last-name>\tSends contact (not necessary telegram user)", NULL},
-  {"send_document", {ca_peer, ca_file_name, ca_none}, do_send_document, "send_document <peer> <file>\tSends document to peer", NULL},
-  {"send_file", {ca_peer, ca_file_name, ca_none}, do_send_file, "send_file <peer> <file>\tSends document to peer", NULL},
+  {"send_document", {ca_peer, ca_file_name, ca_string_end | ca_optional, ca_none}, do_send_document, "send_document <peer> <file>\tSends document to peer", NULL},
+  {"send_file", {ca_peer, ca_file_name, ca_string_end | ca_optional, ca_none}, do_send_file, "send_file <peer> <file>\tSends document to peer", NULL},
   {"send_location", {ca_peer, ca_double, ca_double, ca_none}, do_send_location, "send_location <peer> <latitude> <longitude>\tSends geo location", NULL},
   {"send_photo", {ca_peer, ca_file_name, ca_string_end | ca_optional, ca_none}, do_send_photo, "send_photo <peer> <file> [caption]\tSends photo to peer", NULL},
   {"send_text", {ca_peer, ca_file_name_end, ca_none}, do_send_text, "send_text <peer> <file>\tSends contents of text file as plain text message", NULL},