Extending a scene sequence allows for more complex switching setups, but should also simplify some setups.
Sequences like "A -> B -> A -> C", which previously were only possible by creating a copy of A, can now be specified in a single entry.
To extend a sequence either select the sequence you want to modify and click the extend sequence button or simply double click the entry.
* move addSelectionEntry to AdvSceneSwitcher class and allow select entry to be 'selectable'
Can be useful for implementing 'current transition' as an option or just allowing to select 'None' for screen region ignore
* Add option to select 'current transition'
* use GetWeakSourceName() where possible
* add getCurrentScene() to scene group
* silence OBS warning log and fix typo in audio switch
* extract showing initial status of widgets to function in generic switch
* rework general tab UI
* rework audio tab UI
* rework media tab UI
* rework time tab UI
* rework random tab UI
* rework window tab UI
* rework sreen region tab UI
* rework sequence tab UI
* rework transition tab UI
* adjust log messages to new format
* fix include path and warning
* highlight widgets to guide users (can be disabled)
* add helper frame for screen region tab
* rename main SceneSwitcher widget to AdvSceneSwitcher to resolve naming conflicts with the frontend tools on certain platforms (e.g. Debian 10)
* add media state 'any'
* adjust media switch handling to support vlc source
* move definitions of switcher structs to separate files
* remove useless comment
* cleanup and silence warnings
* add generic switch
* removed delay on main thread startup as it served no purpose
* clean up ultility.hpp
* do not save switchStr to file as it could cause issues when scenes are renamed
* rename sceneRoundTrip to sceneSequence
* add option to switch if window is maximized to title tab
