Removed submodules from internal directories.

Author: technik

.gitmodules

@@ -1,9 +1,3 @@
-[submodule "engine/lib/imgui"]
-	path = engine/lib/imgui
-	url = https://github.com/ocornut/imgui.git
-[submodule "engine/lib/benchmark"]
-	path = engine/lib/benchmark
-	url = https://github.com/google/benchmark.git
 [submodule "include/glm"]
 	path = include/glm
 	url = https://github.com/g-truc/glm.git