docs: updated readme

Author: Sven Ulrich

README.md

@@ -10,7 +10,7 @@
 
 
 ```typescript
- import { StringBuilder, join, format, isNullOrWhiteSpace } from 'typescript-string-operations';
+ import { StringBuilder, emptyString, joinString, formatString, isNullOrWhiteSpace } from 'typescript-string-operations';
  ```
 
 When migrating from Version 1.4.1 or lower, you can also import the class `String`. Using this String class would override the native `String` object from JavaScript. We will remove this declaration with the next major release

package.json

@@ -1,6 +1,6 @@
 {
   "name": "typescript-string-operations",
-  "version": "1.5.0",
+  "version": "1.5.0-rc.15",
   "description": "Simple lightweight string operation library for Typescript, works with Angular",
   "main": "dist/index.js",
   "types": "index.d.ts",