Log the stacktraces of errors when rendering elements in debug mode

common/src/main/kotlin/fr/username404/snowygui/gui/Element.kt

@@ -22,6 +22,7 @@ abstract class Element(
         } catch (t: Throwable) {
             with(Snowy.logs) {
                 error("An element from snowy threw an error: \n\t$t")
+                debug("\t${t.stackTraceToString()}")
                 warn("Rendering of snowy UI elements will now be disabled to avoid further errors.")
                 caughtError = true
             }