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/quat_mult.h

@@ -0,0 +1,33 @@
+// 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_QUAT_MULT_H
+#define IGL_QUAT_MULT_H
+#include "igl_inline.h"
+
+namespace igl
+{
+  // Computes out = q1 * q2 with quaternion multiplication
+  // A Quaternion, q, is defined here as an arrays of four scalars (x,y,z,w),
+  // such that q = x*i + y*j + z*k + w
+  // Inputs:
+  //   q1  left quaternion
+  //   q2  right quaternion
+  // Outputs:
+  //   out  result of multiplication
+  template <typename Q_type>
+  IGL_INLINE void quat_mult(
+    const Q_type *q1, 
+    const Q_type *q2,
+    Q_type *out);
+};
+
+#ifndef IGL_STATIC_LIBRARY
+#  include "quat_mult.cpp"
+#endif
+
+#endif