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

smdpp-data/certs/CertificateIssuer/CI-csr.cnf

@@ -0,0 +1,25 @@
+#openssl x509 extfile params
+extensions = extend
+# This prevent the user to be prompted for values
+prompt = no
+
+distinguished_name = dn-param
+[dn-param] # DN fields
+CN = Test CI
+OU = TESTCERT
+O = RSPTEST
+C = IT
+
+# Extensions for the Test CI 
+[extend] # openssl extensions
+subjectKeyIdentifier = hash
+
+basicConstraints = critical, CA:true
+
+certificatePolicies=critical,2.23.146.1.2.1.0
+
+keyUsage =critical, keyCertSign, cRLSign
+
+subjectAltName = RID:2.999.1
+
+crlDistributionPoints=URI:http://ci.test.example.com/CRL-A.crl, URI:http://ci.test.example.com/CRL-B.crl