Add the ability to remove tracks from Spotify playlists
Fix a bug that makes Vk to be always displayed when trying to show any service's config.
Call stack: SettingsDialog::showEvent -> VkSettingsPage::Load -> VkService::ReloadSettings -> VkService::Logout -> VkService::UpdateRoot -> VkService::ShowConfig
Would probably be better to not call service in VkSettingsPage::Load and read QSettings only, but I don't think it's good either to call ShowConfig when user is being logged-out.