feat(): add clearCache method

Author: ihadeed

README.md

@@ -93,12 +93,15 @@ export class MyMainAppComponent {
 
     // disable spinners by default, you can add [spinner]="true" to a specific component instance later on to override this
     imageLoaderConfig.enableSpinner(false);
+    
+    // set the maximum concurrent connections to 10
+    imageLoaderConfig.setConcurrency(10);
   }
 
 }
 ```
 
-Below are all the methods that the provider has:
+Below are all the methods that the config provider has:
 
 #### enableDebugMode() 
 Enables debug mode to receive console logs, errors, warnings.
@@ -134,6 +137,21 @@ Set a custom directory name to store the cached images in.
 #### setConcurrency(concurrency: number)
 Set the maximum number of concurrent connections. Cached images will be loaded instantly, this limit is only for new images.
 
+# Clearing the cache
+```typescript
+
+import { ImageLoader } from 'ionic-image-loader';
+
+@Component(...)
+class MyComponent {
+  
+  constructor(imageLoader: ImageLoader) {
+    imageLoader.clearCache();
+  }
+  
+}
+
+```
 
 # Contributing
 - **Having trouble?** Create an issue [here](https://github.com/zyramedia/ionic-image-loader/issues/new)

src/providers/image-loader.ts

@@ -52,6 +52,34 @@ export class ImageLoader {
     }
   }
 
+  /**
+   * Clears the cache
+   */
+  clearCache(): void {
+
+    const clear = () => {
+
+      if (!this.isInit) {
+        // do not run this method until our service is initialized
+        setTimeout(clear.bind(this), 500);
+        return;
+      }
+
+      // pause any operations
+      this.isInit = false;
+
+      File.removeRecursively(cordova.file.cacheDirectory, this.config.cacheDirectoryName)
+        .then(() => {
+          this.initCache(true);
+        })
+        .catch(this.throwError.bind(this));
+
+    };
+
+    clear();
+
+  }
+
   /**
    * Downloads an image via cordova-plugin-file-transfer
    * @param imageUrl {string} The remote URL of the image