Refactor traefik with package

Split a bit traefik into package. The idea behind this refactor is to
start move inter-dependencies away and do some DRY or SRP.

- Adds a `provider` package, with providers except `web.go`
- Adds a `types` package with common struct.
- Move `gen.go` to an `autogen` package

Signed-off-by: Vincent Demeester <vincent@sbr.pm>

file.go

@@ -1,70 +0,0 @@
-package main
-
-import (
-	"os"
-	"path/filepath"
-	"strings"
-
-	"github.com/BurntSushi/toml"
-	log "github.com/Sirupsen/logrus"
-	"gopkg.in/fsnotify.v1"
-)
-
-type FileProvider struct {
-	Watch    bool
-	Filename string
-}
-
-func (provider *FileProvider) Provide(configurationChan chan<- configMessage) error {
-	watcher, err := fsnotify.NewWatcher()
-	if err != nil {
-		log.Error("Error creating file watcher", err)
-		return err
-	}
-
-	file, err := os.Open(provider.Filename)
-	if err != nil {
-		log.Error("Error opening file", err)
-		return err
-	}
-	defer file.Close()
-
-	if provider.Watch {
-		// Process events
-		go func() {
-			defer watcher.Close()
-			for {
-				select {
-				case event := <-watcher.Events:
-					if strings.Contains(event.Name, file.Name()) {
-						log.Debug("File event:", event)
-						configuration := provider.LoadFileConfig(file.Name())
-						if configuration != nil {
-							configurationChan <- configMessage{"file", configuration}
-						}
-					}
-				case error := <-watcher.Errors:
-					log.Error("Watcher event error", error)
-				}
-			}
-		}()
-		err = watcher.Add(filepath.Dir(file.Name()))
-		if err != nil {
-			log.Error("Error adding file watcher", err)
-			return err
-		}
-	}
-
-	configuration := provider.LoadFileConfig(file.Name())
-	configurationChan <- configMessage{"file", configuration}
-	return nil
-}
-
-func (provider *FileProvider) LoadFileConfig(filename string) *Configuration {
-	configuration := new(Configuration)
-	if _, err := toml.DecodeFile(filename, configuration); err != nil {
-		log.Error("Error reading file:", err)
-		return nil
-	}
-	return configuration
-}