stat: cached stat race fixed, do not cache at proxy level, elliptics caching is enough
test: updated test to latest elliptics-go version (groups: int32 -> uint32), added bucket update test (bucket which was not present in bucket file)
test: added periodic bucket update test
test: added operation counter statistics test
test: added SIGHUP signal bucket list update
test: print start/complete strings for every test
proxy: turn on all (not only positive) upload results