Initial proof-of-concept SM-DP+ for GSMA consumer eSIM RSP

This commit introduces

* the osmo-smdpp.py program implementing the main procedures and the
  HTTP/REST based ES9+
* python modules for ES8+ and non-volatile RSP Session State storage
* the ASN.1 source files required to parse/encode RSP
* 3GPP test certificates from SGP.26
* an unsigned profile package (UPP) of a SAIP v2.3 TS48 test profile

As I couldn't get the 'Klein' tls support to work, the SM-DP+ code
currently does not support HTTPS/TLS but plan HTTP, so you either have
to modify your LPA to use HTTP instead of HTTPS, or put a TLS proxy in
front.

I have successfully installed an eSIM profile on a test eUICC that
contains certificate/key data within the test CI defined in GSMA SGP.26

Change-Id: I6232847432dc6920cd2bd08c84d7099c29ca1c11

pySim/esim/__init__.py

@@ -0,0 +1,16 @@
+import sys
+from importlib import resources
+
+import asn1tools
+
+def compile_asn1_subdir(subdir_name:str):
+    """Helper function that compiles ASN.1 syntax from all files within given subdir"""
+    asn_txt = ''
+    __ver = sys.version_info
+    if (__ver.major, __ver.minor) >= (3, 9):
+        for i in resources.files('pySim.esim').joinpath('asn1').joinpath(subdir_name).iterdir():
+            asn_txt += i.read_text()
+            asn_txt += "\n"
+    #else:
+        #print(resources.read_text(__name__, 'asn1/rsp.asn'))
+    return asn1tools.compile_string(asn_txt, codec='der')