added solhiny module declaration

apps/solhint/src/index.d.ts

@@ -0,0 +1,5 @@
+declare module 'solhint' {
+  export function processStr (inputStr: any, config?: any, fileName?: string)
+  export function processFile (file: any, config: any)
+  export function processPath (path: any, config: any)
+}