Migrate DevSettings to PluginSettings for much better config flow (#572)

* Add the devsetting config options into settings

* Create dropdown component and add setting controls

* Static dropdwon width and spin arrow

* Improve dropdown option contrast and border

* Forgot to make the settings page respect the static spacing, oops

* Smaller arrow

* Vert padding

* Reset option for settings

* Hide reset button when on default

* Respect the logLevel setting

* Portal settings out to external typechecking module

* Implement new configs using the new singleton Settings

* Remove DevSettings

* Update test runner to use new settings

* More helpful test failure output

* Support non-plugin environment

* Migrate dropdown to new packages system

* Clean up components a tad

plugin/src/Assets.lua

@@ -23,11 +23,15 @@ local Assets = {
 		Icons = {
 			Close = "rbxassetid://6012985953",
 			Back = "rbxassetid://6017213752",
+			Reset = "rbxassetid://10142422327",
 		},
 		Checkbox = {
 			Active = "rbxassetid://6016251644",
 			Inactive = "rbxassetid://6016251963",
 		},
+		Dropdown = {
+			Arrow = "rbxassetid://10131770538",
+		},
 		Spinner = {
 			Foreground = "rbxassetid://3222731032",
 			Background = "rbxassetid://3222730627",