printf() by kernel and servers now send messages to an array of processes,

printf() by kernel and servers now send messages to an array of processes,
OUTPUT_PROCS_ARRAY in <minix/config.h>, in that order, terminated by NONE.
log no longer forwards messages to tty itself. This leads to less funny
loops and more robust debug-message handling. Also the list of
processes receiving messages can easily be changed around or disabled by
editing the array (e.g. disable it by changing the array to { NONE }.).