New provider: Loopia DNS service provider (#2140)

Co-authored-by: Tom Limoncelli <tlimoncelli@stackoverflow.com>

integrationTest/integration_test.go

@@ -915,6 +915,7 @@ func makeTests(t *testing.T) []*TestGroup {
 				"DIGITALOCEAN",  // No paging. Why bother?
 				"CSCGLOBAL",     // Doesn't page. Works fine.  Due to the slow API we skip.
 				"GANDI_V5",      // Their API is so damn slow. We'll add it back as needed.
+				"LOOPIA",        // Their API is so damn slow. Plus, no paging.
 				"MSDNS",         //  No paging done. No need to test.
 				"NAMEDOTCOM",    // Their API is so damn slow. We'll add it back as needed.
 				"NS1",           // Free acct only allows 50 records, therefore we skip

integrationTest/providers.json

@@ -134,6 +134,11 @@
     "domain": "$LINODE_DOMAIN",
     "token": "$LINODE_TOKEN"
   },
+  "LOOPIA": {
+    "username": "$LOOPIA_USERNAME",
+    "password": "$LOOPIA_PASSWORD",
+    "domain": "$LOOPIA_DOMAIN"
+  },
   "LUADNS": {
     "domain": "$LUADNS_DOMAIN",
     "email": "$LUADNS_EMAIL",