fix decimal separator to .
fixes https://github.com/NetEase/Emmagee/issues/31
add uploaded and downloaded bytes
fix kib to mib rounding
fix dev memory output
fix unit output
take first data scan right after starting, last scan when clicking "stop"
clean up creating human readable strings (b, kib, mib) a little
replaced net traffic with up and download traffic in GUI
only send mail if sender set
fix sorting
removed battery from GUI