Add Kaikas browser wallet support (#54)

connectors/kaikas.ts

@@ -0,0 +1,27 @@
+import LockConnector from '../src/connector';
+
+export default class Connector extends LockConnector {
+  async connect() {
+    let provider;
+    if (window['klaytn']) {
+      provider = window['klaytn'];
+      try {
+        await window['klaytn'].enable();
+      } catch (e) {
+        console.error(e);
+        // Return when the error is Error: User denied account authorization
+        if (e.code === -32603) return;
+      }
+    } else if (window['caver']) {
+      provider = window['caver'].currentProvider;
+    }
+    return provider;
+  }
+
+  async isLoggedIn() {
+    if (!window['klaytn']) return false;
+    if (window['klaytn'].selectedAddress) return true;
+    await new Promise((r) => setTimeout(r, 400));
+    return !!window['klaytn'].selectedAddress;
+  }
+}