Implement alert for unsaved changes

[jackyzy823]

For #296

There's two model: 1) Tracking if changed (not very accurately ie: Enable and disable and then enable is still treated as changed) 2) Comparison between current and original

It looks like SmartProxy has implemented some basic objection for tracking (settingsPage.changeTracking). So I use the tracking model for most changes.

However , it's hard/(too complex) to apply tacking model on GeneralOptions , But comparison is suitable here.

---

Tracking	Action	Element	Status
activeProxy	Change Profile	cmbActiveProxyServer	DONE
smartProfiles	Edit profilename	txtSmartProfileName	DONE
smartProfiles	Toggle Enable/Disable	chkSmartProfileEnabled	DONE
smartProfiles	Choose Profile's Proxy Server	cmbProfileProxyServer	DONE
smartProfiles	Add/Edit rule	btnSubmitRule	DONE
smartProfiles	Add multiple rules	btnSubmitMultipleRule	DONE
smartProfiles	Import rule	btnImportRules	DONE
smartProfiles	Remove rule	btnRulesRemove	DONE
smartProfiles	Clear all rules	btnClearProxyRules	DONE
smartProfiles	Delete multiple rules	btnRemoveMultipleProxyRule	DONE in #341
rulesSubscriptions	Subscribe/Edit a rules list	btnSaveRulesSubscriptions	Already
rulesSubscriptions	Delete rules list	btnRuleSubscriptionsRemove	Already
rulesSubscriptions	Clear all rules lists	btnClearRulesSubscriptions	Already
rulesSubscriptions	Refresh rules list	btnRuleSubscriptionsRefresh	Already
rulesSubscriptions	Delete multiple rules	btnRemoveMultipleRulesSubscription	DONE in #341
servers	Add/Edit server	btnSubmitProxyServer	Already
servers	Delete server	btnServersRemove	Already
servers	Clear all servers	btnClearProxyServers	Already
servers	Import server	btnImportProxyServer	DONE
servers	Delete multiple servers	btnRemoveMultipleProxyServer	DONE in #341
serverSubscriptions	Subscribe list	btnSaveServerSubscription	Already
serverSubscriptions	Delete list	btnSubscriptionsRemove	Already
serverSubscriptions	Clear all lists	btnClearServerSubscriptions	Already
serverSubscriptions	Delete multiple lists	btnRemoveMultipleServerSubscription	DONE in #341
SPECIAL	Import server backup	btnImportProxyServer	SAME as Import server
SPECIAL	Restore backup	btnRestoreBackup	IGNORE unsaved changes by removing eventListenr
SPECIAL	Factory Reset	btnFactoryReset	IGNORE unsaved changes by removing eventListenr
SPECIAL	Delete a profile	btnDeleteSmartProfile	NOTHING (because runtime message is send directly)
SPECIAL	Add a new profile		if user choose to save when staying , try save it (intent to fail if profile title is empty)

Also changeTracking to false when runtimeSendMessage(SettingsPageSave*) is called.

Note:
changeTracking .rulesSubscriptions should also set to false in onClickSaveSmartProfile ( same as changeTracking.smartProfile )

[salarcode]

Thanks for this, I will check it soon.
I wish if you were to work on a feature request you worked on something higher priority, like these:
#273 , #317 , #342 and etc
If you want to work on anything please let me know I'll refine the issue details

[jackyzy823]

I may work on #273 , but implementation details should be discussed. (like export in what format or etc...)

I really don't understand what #317 is for.
I won't work on #342 , because i don't have any mac devices.

Currently i'm working on SwitchyOmega import related stuff like #318.

[salarcode]

Thanks. I have already started working on #318 , #286 so that one is not needed. Lots of requests for it recently

[jackyzy823]

Well, we could discuss some implementation details.
I'll add some comments under #286

[salarcode]

This method is not gonna work well. Settings could come from different locations like sync, backups and etc and might miss some properties.
This method should treat null/undefined and empty values as same

[salarcode]

with neq function it should now

[salarcode]

I'm not happy to keep a reference of pageSmartProfile in the page level, we can be more smart about this.

[jackyzy823]

Yes, i don't like this too, but i couldn't find a way to find if there's an unsaved profile (and get its page object) when leaving the page.

[salarcode]

Thanks for the write up, overall looking good but I've left some comments.

I've pushed a clean up commit as well. Please fix the conflicts while you are at it