Update routes

Author: quietbits

routes.txt

@@ -539,6 +539,9 @@
 /docs/tools/lab/api-explorer/horizon-endpoint
 /docs/tools/lab/api-explorer/rpc-methods
 /docs/tools/lab/quickstart-with-lab
+/docs/tools/lab/smart-contracts
+/docs/tools/lab/smart-contracts/contract-explorer
+/docs/tools/lab/smart-contracts/smart-contract-list
 /docs/tools/lab/transactions
 /docs/tools/quickstart
 /docs/tools/quickstart/advanced-usage