move data directory constant to config file

scraping/config.R

@@ -0,0 +1,2 @@
+DOWNLOAD_DIR = "../data/" # warning: this is not created (should maybe)
+

scraping/fetch.R

@@ -1,9 +1,8 @@
 source("../utils/helpers.R")
+source("config.R")
 library(RCurl)
 library(stringr)
 
-DOWNLOAD_DIR = "../data/" # warning: this is not created (should maybe)
-
 mk_absolute_url <- function(path) paste0("https://www.bundestag.de", path)
 
 mk_url <- function(offset) {