improved doc

Former-commit-id: 0fe04ba499a40fc8c0f4850122862abfa471aaac

include/igl/is_border_vertex.cpp

@@ -11,7 +11,9 @@
 #include "triangle_triangle_adjacency.h"
 
 template <typename DerivedV, typename DerivedF>
-IGL_INLINE std::vector<bool> igl::is_border_vertex(const Eigen::PlainObjectBase<DerivedV> &V, const Eigen::PlainObjectBase<DerivedF> &F)
+IGL_INLINE std::vector<bool> igl::is_border_vertex(
+    const Eigen::PlainObjectBase<DerivedV> &V, 
+    const Eigen::PlainObjectBase<DerivedF> &F)
 {
   Eigen::PlainObjectBase<DerivedF> FF;
   igl::triangle_triangle_adjacency(V,F,FF);

include/igl/is_border_vertex.h

@@ -22,7 +22,8 @@ namespace igl
   //   F  #F by 3 list of triangle indices
   // Returns #V vector of bools revealing whether vertices are on boundary
   //
-  // Known Bugs: does not depend on V
+  // Known Bugs: - does not depend on V
+  //             - assumes mesh is edge manifold
   // 
   template <typename DerivedV, typename DerivedF>
   IGL_INLINE std::vector<bool> is_border_vertex(