Mod Options panel has no scroll bar

[Cosine256]

The Mod Options panel has no visible scroll bar, even if the options extend past the bottom of the panel. This happens with script mods with a lot of options, such as Randomizer. Scrolling with the mouse wheel still works.

I believe this is being caused by the combination flag ImGuiWindowFlags_NoDecoration on the ImGui window:

Playlunky/source/playlunky/mod/mod_manager.cpp

Lines 1026 to 1029 in 08628db

	ImGui::Begin(
	"Mod Options",
	nullptr,
	ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoResize | ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoDecoration);

That flag is redundant with the others, since NoTitleBar, NoResize, and NoCollapse are already explicitly set on the window, so all it serves to do is add NoScrollbar.

[Dregu]

Enabled scrollbars and other window controls in #51