catch up with api and system changes in libpcp. added c++ buffer class as well

TODO

@@ -20,6 +20,13 @@ enable formats for secret key exports as well
 
 Unitttests:
   - sometimes "no matching pub key in vault, while it's there
+    Cause:
+      echo HALLO | ../src/pcp1 -V vcl -e -O testencrypted -i 0xA907B927849B39F9
+        ok 28 - check-crypto-unencrypted-secret-message
+      public key exported.  <=== ???
+
+
+
   - sometimes secret key is empty