Signed-off-by: Etienne Champetier <champetier.etienne@gmail.com>

As prometheus-node-exporter-lua is a reimplementation of node_exporter,
I'm using "collector" instead of "scraper" and renaming some collectors

put each collector in a separate file

report collector success/failure and duration per scrape
(follow https://github.com/prometheus/node_exporter/pull/516)

allow to filter collectors using "collect[]" params
(see https://github.com/prometheus/node_exporter#filtering-enabled-collectors)

Signed-off-by: Etienne Champetier <champetier.etienne@gmail.com>

On my bullet m2, scrape duration goes from between 0.2 and 0.5 to a stable 0.025
We also don't depend on luci anymore

This remove wifi_network_up metric, but this metric was buggy
wifi_network_up{ifname="wlan0-1",ssid="test1",channel="11",mode="Master",bssid="12:34:56:78:9A:BC",country="FR",frequency="2.462"} 1
wifi_network_up{ifname="radio0.network2",ssid="test1",channel="11",mode="Master",country="US",frequency="2.462"} 0

Signed-off-by: Etienne Champetier <champetier.etienne@gmail.com>

Signed-off-by: Etienne Champetier <champetier.etienne@gmail.com>

Testing on a bullet m2, uname collector was taking on average 0.12
it now takes 0.0007

Signed-off-by: Etienne Champetier <champetier.etienne@gmail.com>

also reduce calls to output()

Signed-off-by: Etienne Champetier <champetier.etienne@gmail.com>

Signed-off-by: Christian Simon <simon@swine.de>