Add SetAccountURI method to ACME client

Signed-off-by: James Munnelly <james@munnelly.eu>

third_party/crypto/acme/acme.go

@@ -90,6 +90,15 @@ type Client struct {
 	accountURL string
 }
 
+// SetAccountURL will set the account URL cached by the client.
+// This should be used with caution, in order to reduce the number of calls
+// made to the 'new-acct' endpoint in 'cacheAccountURL'
+func (c *Client) SetAccountURL(url string) {
+	c.urlMu.Lock()
+	defer c.urlMu.Unlock()
+	c.accountURL = url
+}
+
 // Discover performs ACME server discovery using c.DirectoryURL.
 //
 // It caches successful result. So, subsequent calls will not result in