yargs: add conflicts()

yargs/index.d.ts

@@ -109,6 +109,9 @@ declare namespace yargs {
         config(key: string, parseFn: (configPath: string) => Object): Argv;
         config(keys: string[], parseFn: (configPath: string) => Object): Argv;
 
+        conflicts(key: string, value: string): Argv;
+        conflicts(conflicts: { [key: string]: string }): Argv;
+
         wrap(columns: number): Argv;
 
         strict(): Argv;

yargs/yargs-tests.ts

@@ -599,3 +599,12 @@ function Argv$demandOption() {
         .demandOption(['a', 'b'], true)
         .argv;
 }
+
+function Argv$conflicts() {
+    var ya = yargs
+        .conflicts('a', 'b')
+        .conflicts({
+            a: 'b'
+        })
+        .argv;
+}