pySim.globalplatform: Add 'http' submodule for GP Amd B RAM over HTTPS

This implements the first parts of the "GlobalPlatform Remote
Application Management over HTTP Card Specification v2.3 - Amendment B,
Versoin 1.2".  Specifically, this patch covers the TLV definitions for
the OTA message used for HTTPS session triggering.

This also adds some more unit test coverage to pySim.cat, based on
real-world data that was captured nested inside the HTTPS Administration
session triggering parameters.

Change-Id: Ia7d7bd6df41bdf1249011bad9a9a38b7669edc54

tests/test_tlvs.py

@@ -31,6 +31,7 @@ import pySim.sysmocom_sja2
 import pySim.gsm_r
 import pySim.cdma_ruim
 import pySim.global_platform
+import pySim.global_platform.http
 
 if 'unittest.util' in __import__('sys').modules:
     # Show full diff in self.assertEqual.