Added timedelta

Added timedelta to choose the time interval for every request, this speed up the process

tweep.py

@@ -447,7 +447,7 @@ async def main():
     init = -1
     num = 0
     while _since < _until:
-        arg.since = str(_until - datetime.timedelta(days=1))
+        arg.since = str(_until - datetime.timedelta(days=int(arg.timedelta)))
         arg.until = str(_until)
         '''
         If our response from getFeed() has an exception,
@@ -458,7 +458,7 @@ async def main():
             feed, init, count = await getTweets(init)
             num += count
         else:
-            _until = _until - datetime.timedelta(days=1)
+            _until = _until - datetime.timedelta(days=int(arg.timedelta))
             feed = [-1]
         # Control when we want to stop scraping.
         if arg.limit is not None and num >= int(arg.limit):
@@ -509,6 +509,7 @@ if __name__ == "__main__":
     ap.add_argument("-l", help="Serch for Tweets in a specific language")
     ap.add_argument("-o", help="Save output to a file.")
     ap.add_argument("-es", "--elasticsearch", help="Index to Elasticsearch")
+    ap.add_argument("-t", "--timedelta", help="Time intervall for every request")
     ap.add_argument("--year", help="Filter Tweets before specified year.")
     ap.add_argument("--since", help="Filter Tweets sent since date (Example: 2017-12-27).")
     ap.add_argument("--until", help="Filter Tweets sent until date (Example: 2017-12-27).")