added some debug output, and resolved a bug in the filesys thread such that it only services one outgoing chunk request per thread loop. if I do it until the loop is exhausted, on a local network it will never exit the while loop until the file xfer is done. this is casued by the new credit system I instroduce. 50 pending, 1 done, 1 new requested. These came in just as fast or faster than going out, so that while loop looped until eof