wffweb-12.0.9 release changes

[webfirmframework]

• Major improvements to lossess communication. A manual ping-pong is implemented for reliable websocket reconnection. This can prevent when user switches from one network to another or physical connection loss, eg: When user switches from WIFI to 2G/3G/4G/5G network. The heartbeat timeout value can be set by setWebSocketHeartbeatTimeout in BrowserPage. The default heartbeat timeout value is 10000 milliseconds.
• A bug fix related to losses communication (rarest possible bug).
• Better handling for browserPage removal from BrowserPageContent on browser page close or related scenarios.
• New methods in AbstractHtml tag class - getParentChildLinkedTags, getNextSibling, getPreviousSibling.
• JavaScript security improvements to avoid wff objects mutation/deletion. This will prevent other JavaScript files in the browser to mutating/deleting the wffweb JavaScript objects.
• New method toOutputStream in JSON parser classes. The toBigJsonString is also available for JsonListNode, it's a common method in JsonBaseNode class.