handle choose file callback in android

updated locationchange iOS javascript event name, updated javaScriptHandlerForbiddenNames dart variable

Added shouldInterceptAjaxRequest, onAjaxReadyStateChange, onAjaxProgressEvent and shouldInterceptFetchRequest events, added useShouldInterceptAjaxRequest and useShouldInterceptFetchRequest webview options, updated node.js server test, added injectJavascriptFileFromAsset and injectCSSFileFromAsset methods, renamed some methods

updated webview options classes, fixed debuggingEnabled, added getTRexRunnerHtml and getTRexRunnerCss methods

added getHtml method, updated android config, remove block on long press webview android, fixed other issues

added onReceivedServerTrustAuthRequest and onReceivedClientCertRequest events to manage SSL requests, added clearSslPreferences and clearClientCertPreferences for Android, added nodejs_server_test_auth_basic_and_ssl for testing auth and ssl requests

updated android safe browsing, updated ios browser and SafariViewController options, added onSafeBrowsingHit event for android

Added ,  (available only for Android), Added ,  and  events to manage javascript popup dialogs only for Android now, added support for javascript dialogs popups for iOS

Added new WebView option minimumFontSize, Added new Android WebView options, Added new iOS WebView options, Added onGeolocationPermissionsShowPrompt event and GeolocationPermissionShowPromptResponse class (available only for Android), updated Android ContentBlocker, updated Android build.gradle compileSdkVersion 29

Updated onLoadResource event, Updated WebResourceResponse class, Deleted WebResourceRequest class, added useOnDownloadStart option, created webview options classes, added initial content blocking support

added onDownloadStart event, onLoadResourceCustomScheme event and resourceCustomSchemes option, onTargetBlank event and useOnTargetBlank option, code refactoring

updated plugin version, added new options to hide/show scrollbars #165, initial support for DownloadManager in Android and iOS

Update readme example

migrating to swift 5.0

Fix abstract method error  && swift version error

Create issue and pull request templates 

Resolving gradle error.

Android takeScreenshot does not work properly.

Remove async call in close Swift

Avoid null pointer exception after webview is disposed

Column does not accept null widget