Building igl statically and moving to the dep scripts

Fixing dep build script on Windows and removing some warnings.

Use bundled igl by default.

Not building with the dependency scripts if not explicitly stated. This way, it will stay in
Fix the libigl patch to include C source files in header only mode.

src/libigl/igl/random_dir.h

@@ -0,0 +1,31 @@
+// This file is part of libigl, a simple c++ geometry processing library.
+// 
+// Copyright (C) 2013 Alec Jacobson <alecjacobson@gmail.com>
+// 
+// This Source Code Form is subject to the terms of the Mozilla Public License 
+// v. 2.0. If a copy of the MPL was not distributed with this file, You can 
+// obtain one at http://mozilla.org/MPL/2.0/.
+#ifndef IGL_RANDOM_DIR_H
+#define IGL_RANDOM_DIR_H
+#include "igl_inline.h"
+
+#include <Eigen/Core>
+
+namespace igl
+{
+  // Generate a uniformly random unit direction in 3D, return as vector
+  IGL_INLINE Eigen::Vector3d random_dir();
+  // Generate n stratified uniformly random unit directions in 3d, return as rows
+  // of an n by 3 matrix
+  //
+  // Inputs:
+  //   n  number of directions
+  // Return n by 3 matrix of random directions
+  IGL_INLINE Eigen::MatrixXd random_dir_stratified(const int n);
+}
+
+#ifndef IGL_STATIC_LIBRARY
+#  include "random_dir.cpp"
+#endif
+
+#endif