Fixed comparison against few function arguments from using strict equality === with null to equality == as undefined values wouldnt cause the default values to be assigned which could cause leaks as cleanup wouldnt get triggered and default zOrdering wouldnt be set properly
fixed #2074: Scene init twice bug
Merge pull request #888 from tomasztunik/master

Fix in logical comparisons of undefined argument values against `null` for setting default argument values
Merge pull request #889 from ShengxiangChen/issue2074

fixed #2074: Scene init twice bug
fixed #890 folder has been renamed from "Draw_Nodes"  to "draw_nodes"
fixed #890 folder has been rename from "Draw_Nodes" to "draw_nodes"
Merge pull request #892 from dingpinglv/Iss890_RenameFolderName

fixed #890 folder has been renamed from "Draw_Nodes" to "draw_nodes"