closes#263
- Rename dialog to dialogue
- Give meaningful name to generic actors
- Move combat screen content to turn_combat folder
- Add new icon.png and .svg
- Change combat UI to not emit a signal from its parent, instead pass parameters to a function and let the combat work on them there
- Remove UI accessing deep layers on the hierarchy (get_parent().get_node("../etc/etc../etc...")
- Fix defend() stacking, making the player invulnerable, now evey turn the Health.armor resets to a base_armor value
- Remove useless Inventory button (maybe added again in the future when an inventory is added to the demo)
