configure: Load fetcher plugins after crypto base plugins

Some fetcher plugins (such as curl) might build upon OpenSSL to implement
HTTPS fetching. As we set (and can't unset) threading callbacks in our
openssl plugin, we must ensure that OpenSSL functions don't get called after
openssl plugin unloading.

We achieve that by loading curl and all other fetcher plugins after the base
crypto plugins, including openssl.

testing/tests/ikev2/multi-level-ca-loop/hosts/carol/etc/strongswan.conf

@@ -1,5 +1,5 @@
 # /etc/strongswan.conf - strongSwan configuration file
 
 charon {
-  load = curl aes des sha1 sha2 md5 pem pkcs1 gmp random nonce x509 revocation hmac xcbc stroke kernel-netlink socket-default
+  load = aes des sha1 sha2 md5 pem pkcs1 gmp random nonce x509 curl revocation hmac xcbc stroke kernel-netlink socket-default
 }

testing/tests/ikev2/multi-level-ca-loop/hosts/moon/etc/strongswan.conf

@@ -1,5 +1,5 @@
 # /etc/strongswan.conf - strongSwan configuration file
 
 charon {
-  load = curl aes des sha1 sha2 md5 pem pkcs1 gmp random nonce x509 revocation hmac xcbc stroke kernel-netlink socket-default
+  load = aes des sha1 sha2 md5 pem pkcs1 gmp random nonce x509 curl revocation hmac xcbc stroke kernel-netlink socket-default
 }