Add test for EC keys with all curves.

(Made possible by the OID fix.)
diff --git a/tests/data_files/ec_384_pub.pem b/tests/data_files/ec_384_pub.pem
new file mode 100644
index 0000000..de95382
--- /dev/null
+++ b/tests/data_files/ec_384_pub.pem
@@ -0,0 +1,5 @@
+-----BEGIN PUBLIC KEY-----
+MHYwEAYHKoZIzj0CAQYFK4EEACIDYgAE2cZitQuinKR5kEUOBDrq9PDGmxVnbREv
+YipxyTBZr5mWkcVoDStE0RFXnbEvSkE6LtXEX8+2e1tj4AuR6+WdCaaxrCwMQoKq
+EjF+1ZFPmZvEiLsTLoNCzDbyyl4zecdH
+-----END PUBLIC KEY-----