Merge pull request #199 from jrenner/master

fix bits/bytes calculation
Merge pull request #202 from jrenner/master

fixed crash bug related to custom port with '-p' arg
Merge pull request #203 from jrenner/master

add time_since_update to netstats (let API users calc net bytes/s)
Solve issue #206 / Server port in client mode
Merge pull request #216 from jrenner/master

implement time_since_update for disk and processes