Add hwmon /sensors support (#278)

* Add hwmon support (mainly known from lm-sensors)

This commit adds initial support for linux hardware sensors, exported
through sysfs.

Details of the interface can be found at
https://www.kernel.org/doc/Documentation/hwmon/sysfs-interface

* Add end-to-end test with some real life data

* Cleanup comments on hwmon collector

* Drop raw sensor name from hwmon output

* Let the sensor label be "sensor"

* Add hwmon short description to README.

1 files changed, 1 insertions, 1 deletions

diff --git a/node_exporter.go b/node_exporter.go
index 1e5594a..52d76b4 100644
--- a/node_exporter.go
+++ b/node_exporter.go
@@ -31,7 +31,7 @@ import (
 )
 
 const (
-        defaultCollectors = "conntrack,cpu,diskstats,entropy,filefd,filesystem,loadavg,mdadm,meminfo,netdev,netstat,sockstat,stat,textfile,time,uname,vmstat"
+        defaultCollectors = "conntrack,cpu,diskstats,entropy,filefd,filesystem,hwmon,loadavg,mdadm,meminfo,netdev,netstat,sockstat,stat,textfile,time,uname,vmstat"
 )
 
 var (