News features and improvements (#8)

* added config file implementation, refactoring

* add gitignore

* improved test

* preperations for more metrics

* added resource metrics

* added first bgp metrics

* added asn as label for bgp metrics

* added prefix and message counts to bgp metrics

* simplified

* Update README.md

* added yaml dependency

* fixed go routine call

* added timeout

* clean up

* added TLS support

* set default api port for TLS

* added routes metric

* added missing log information

config/config.go

@@ -0,0 +1,34 @@
+package config
+
+import (
+	"io"
+	"io/ioutil"
+
+	yaml "gopkg.in/yaml.v2"
+)
+
+type Config struct {
+	Devices []Device `yaml:"devices"`
+}
+
+type Device struct {
+	Name     string `yaml:"name"`
+	Address  string `yaml:"address"`
+	User     string `yaml:"user"`
+	Password string `yaml:"password"`
+}
+
+func Load(r io.Reader) (*Config, error) {
+	b, err := ioutil.ReadAll(r)
+	if err != nil {
+		return nil, err
+	}
+
+	c := &Config{}
+	err = yaml.Unmarshal(b, c)
+	if err != nil {
+		return nil, err
+	}
+
+	return c, nil
+}