Using admin api, instead open port (#1)

* influxdb2 integration
* using python alpine base image
* add authorization, refactoring config
* logging instead print, keenetic api exception handling when try to collect metrics, a little pep8

config/config.ini.sample

@@ -0,0 +1,13 @@
+[influxdb]
+host=<HOST>
+port=80
+username=admin
+password=<INFLUX_PASS>
+db=keenetic
+[keenetic]
+admin_endpoint=http://192.168.1.1:80
+skip_auth=false
+login=admin
+password=<KEENETIC_PASS>
+[collector]
+interval_sec=30

config/influx.json.sample

@@ -1,9 +0,0 @@
-{
-  "influxdb": {
-    "host": "<HOST>",
-    "port": 80,
-    "username": "admin",
-    "password": "<PASS>",
-    "db": "keenetic"
-  }
-}

config/metrics.json

@@ -1,6 +1,4 @@
 {
-  "endpoint" : "http://192.168.1.1:79/rci",
-  "interval_sec" : 30,
   "metrics" : [
     {
       "command": "processes",