fixup! task-0*: various updates

Author: crasbe

task-02/README.md

@@ -15,10 +15,12 @@ an error occurs.
 
 Shell commands need to be added manually to the shell on initialization,
 usually this is done with the macro command `SHELL_COMMAND()`.
+Please note that the command name is *not* written in quotes and can not have
+any whitespaces!
 ```c
 #include "shell.h"
 
-SHELL_COMMAND("command name", "command description", cmd_handler);
+SHELL_COMMAND(command_name, "command description", cmd_handler);
 
 /* ... */
     shell_run(NULL, line_buf, SHELL_DEFAULT_BUFSIZE)

task-06/main.c

@@ -10,8 +10,8 @@ static msg_t _main_msg_queue[MAIN_QUEUE_SIZE];
 extern int udp_send(int argc, char **argv);
 extern int udp_server(int argc, char **argv);
 
-SHELL_COMMAND("udp", "send udp packets", udp_send);
-SHELL_COMMAND("udps", "start udp server", udp_server);
+SHELL_COMMAND(udp, "send udp packets", udp_send);
+SHELL_COMMAND(udps, "start udp server", udp_server);
 
 int main(void)
 {

task-09/main.c

@@ -36,7 +36,7 @@ static msg_t _main_msg_queue[MAIN_QUEUE_SIZE];
 
 extern int udp_cmd(int argc, char **argv);
 
-SHELL_COMMAND("udp", "send data over UDP and listen on UDP ports", udp_cmd);
+SHELL_COMMAND(udp, "send data over UDP and listen on UDP ports", udp_cmd);
 
 #ifdef MODULE_GNRC_SIXLOWPAN
 static char _stack[THREAD_STACKSIZE_MAIN];