exp: set default size of edict references window

* default width is 400
* default height is adjusted automatically depending on content

Misc/qs_pak/scripts/expmode_edicts.lua

@@ -497,6 +497,7 @@ function expmode.edicts.references(edict)
 
 	local function oncreate(self)
 		self:setconstraints()
+		self:setsize(imVec2(400, 0))
 		self.edict = edict
 		self.edictid = edictid
 	end