slider.d.ts has wrong import syntax

[jon-smith]

I'm submitting a ...

[x] bug report

Current behavior
When importing a primereact Slider into a typescript file import { Slider } from 'primereact/slider'; compilation fails with error
(1,1) Statements are not allowed in ambient contexts.

Expected behavior
Compilation should not fail.

Potential fix (Happy to put this in as a pull request if that helps.)
If I replace the contents of primereact/slider.d.ts with
export * from 'primereact/components/slider/Slider';
then it compiles file. This is consistent with all other d.ts files I've seen.

Minimal reproduction of the problem with instructions
In a .tsx file:
import { Slider } from 'primereact/slider';
tsconfig.json:
{ "compilerOptions": { "baseUrl": ".", "outDir": "build/dist", "module": "esnext", "target": "es5", "lib": [ "es6", "dom", "es2018" ], "sourceMap": true, "allowJs": true, "jsx": "react", "moduleResolution": "node", "rootDir": "src", "forceConsistentCasingInFileNames": true, "noImplicitReturns": true, "noImplicitThis": true, "noImplicitAny": true, "strictNullChecks": true, "suppressImplicitAnyIndexErrors": true, "noUnusedLocals": false, "allowSyntheticDefaultImports": true }, "exclude": [ "node_modules", "build", "scripts", "acceptance-tests", "webpack", "jest", "src/setupTests.ts" ], "include": [ "./src/**/*" ] }

Please tell us about your environment:
Windows 10, Visual Studio Code, npm

• React version:
  16.6.3

• PrimeReact version:
  2.0.1

• Language:
  TypeScript 3.2.1