Migrate over to using pyosmocom

We're creating a 'pyosmocom' pypi module which contains a number of core
Osmocom libraries / interfaces that are not specific to SIM card stuff
contained here.

The main modules moved in this initial step are pySim.tlv, pySim.utils
and pySim.construct. utils is split, not all of the contents is
unrelated to SIM Cards.  The other two are moved completely.

Change-Id: I4b63e45bcb0c9ba2424dacf85e0222aee735f411

pySim/cards.py

@@ -23,10 +23,11 @@
 #
 
 from typing import Optional, Tuple
+from osmocom.utils import *
+
 from pySim.ts_102_221 import EF_DIR, CardProfileUICC
 from pySim.ts_51_011 import DF_GSM
-
-from pySim.utils import *
+from pySim.utils import SwHexstr
 from pySim.commands import Path, SimCardCommands
 
 class CardBase: