Builder manager bugfixes (#367)

This contains a few different builder manager fixes:

* Update the zip file structure to avoid an extra subdirectory
* Annotate packages with what functions are using them
* Only trigger builds when there is no deployment archive
* Python environment loadpath bugfixes
* Other bugfixes

environments/fetcher/fetcher.go

@@ -152,13 +152,11 @@ func (fetcher *Fetcher) FetchHandler(w http.ResponseWriter, r *http.Request) {
 		http.Error(w, err.Error(), 400)
 		return
 	}
-	log.Printf("fetcher received fetch request: %v", req)
+	log.Printf("fetcher received fetch request and started downloading: %v", req)
 
 	tmpFile := req.Filename + ".tmp"
 	tmpPath := filepath.Join(fetcher.sharedVolumePath, tmpFile)
 
-	log.Printf("Start downloading...")
-
 	if req.FetchType == FETCH_URL {
 		// fetch the file and save it to the tmp path
 		err := downloadUrl(req.Url, tmpPath)
@@ -283,7 +281,7 @@ func (fetcher *Fetcher) UploadHandler(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	log.Println("Start uploading...")
+	log.Println("Starting upload...")
 	ssClient := storageSvcClient.MakeClient(req.StorageSvcUrl)
 
 	fileID, err := ssClient.Upload(dstFilepath, nil)