PEP8 style

[syncle]

Changing python function names to comply with PEP8 style.

[qianyizh]

Only two minor comments.

One additional thing:
Can we add a simple license note at the beginning of each py file, something like:

# Open3D: www.open3d.org
# The MIT License (MIT)
# See license file or visit www.open3d.org for details

[qianyizh]

 		.def_readonly_static("PrimeSenseDefault",
 				&PinholeCameraIntrinsic::PrimeSenseDefault)

This should also be changed to the same naming convention. See this:
https://www.python.org/dev/peps/pep-0008/#method-names-and-instance-variables

[qianyizh]

 	py::class_<GlobalOptimizationLevenbergMarquardt,
 			PyGlobalOptimizationMethod<GlobalOptimizationLevenbergMarquardt>,
 			GlobalOptimizationMethod> global_optimization_method_LM(m,
 			"GlobalOptimizationLevenbergMarquardt");
 	py::detail::bind_default_constructor<GlobalOptimizationLevenbergMarquardt>
 			(global_optimization_method_LM);
 	py::detail::bind_copy_functions<GlobalOptimizationLevenbergMarquardt>(
 			global_optimization_method_LM);
 	global_optimization_method_LM
 			.def("__repr__", [](const GlobalOptimizationLevenbergMarquardt &te) {
 			return std::string("GlobalOptimizationLevenbergMarquardt");
 	});

LM -> lm