improve up/down rate  calculation efficiency
replaced setTimeout/0 with process.nextTick, more calls with process.nextTick (temporary fix), additional logging
experimental changes: increase peer MAX_REQUESTS to 25, decrease KEEPALIVE_PERIOD to 10 secs
Merge branch 'master' of github.com:iantocristian/node-torrent-client
reverting to setTimeout/0 as it appears to be faster than process.nextTick
added processutils nextTick wrapper
piece data handling updates: added write buffer, fixed code in setData to avoid redundant isValid calls, use buffered data for validation when available
Merge pull request #1 from iantocristian/master

some fixes and improvements