Update procstats.py to send proc.meminfo.* in bytes rather than KB

procstats reads in /proc/meminfo but the units specified are in kB.
This change checks for kB as a unit and multiplies by 1000.
```
root@server:~# cat /proc/meminfo 
MemTotal:        8200352 kB
MemFree:         4417708 kB
```

This makes it nicer to graph with a format string of ``%.1s%cB`` 
Currently OpenTSDB is incorrectly showing MB instead of GB

PS
Appears to always be kB in Linux
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/filesystems/proc.txt