[age restriction] progress 14/n - withdraw and deposit

Age restriction support for
  - withdraw is done and tested
  - deposit is done and tested

TODOs:
  - melt/refresh/reveal
  - link

------

Added functions
 - TALER_age_restriction_commit
 - TALER_age_commitment_derive
 - TALER_age_commitment_hash
 - TALER_age_restriction_commitment_free_inside
 - Hash of age commitment passed around API boundaries

Exchangedb adjustments for denominations
 - all prepared statements re: denominations now handle age_mask
 - signature parameters adjusted

Hash and signature verification of /keys adjusted
 - Hashes of (normal) denominations and age-restricted denominations are
   calculated seperately
 - The hash of the age-restricted ones will then be added to the other
   hash
 - The total hash is signed/verified

Tests for withdraw with age restriction added
 - TALER_EXCHANGE_DenomPublickey now carries age_mask
 - TALER_TESTING_cmd_withdraw_amount* takes age parameter
 - TALER_TESTING_find_pk takes boolean age_restricted
 - WithdrawState carries age_commitment and its hash
 - withdraw_run derives new age commitment, if applicable
 - Added age parameter to testing (13 as example)

Various Fixes and changes
 - Fixes of post handler for /management/extensions
 - Fixes for offline tool extensions signing
 - Slight refactoring of extensions
 - Age restriction extension simplified
   - config is now global to extension
   - added global TEH_age_restriction_enabled and TEH_age_mask in
     taler-exchange-httpd
   - helper functions and macros introduced

1 files changed, 2 insertions, 2 deletions

diff --git a/src/lib/exchange_api_management_post_extensions.c b/src/lib/exchange_api_management_post_extensions.c
index c0ab143f6..87b0e0be8 100644
--- a/src/lib/exchange_api_management_post_extensions.c
+++ b/src/lib/exchange_api_management_post_extensions.c
@@ -151,7 +151,7 @@ TALER_EXCHANGE_management_post_extensions (
   body = GNUNET_JSON_PACK (
     GNUNET_JSON_pack_object_steal ("extensions",
                                    ped->extensions),
-    GNUNET_JSON_pack_data_auto ("extensions_sigs",
+    GNUNET_JSON_pack_data_auto ("extensions_sig",
                                 &ped->extensions_sig));
 
   eh = curl_easy_init ();
@@ -168,7 +168,7 @@ TALER_EXCHANGE_management_post_extensions (
     return NULL;
   }
   json_decref (body);
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
               "Requesting URL '%s'\n",
               ph->url);
   GNUNET_assert (CURLE_OK == curl_easy_setopt (eh,