Remove deprecated functions (#2234)

* basic config file

* documentation for two funcs

* better theme; subnamespace

* A-c

* documentation for all core headers

* more documentation

* documentation for all headers (except a few classes)

* rm accidental comment on igl

* just h

* typo

* accidental delete

* fix compile issues

* add main page [ci skip]

* relative include paths

* relative include paths

* inexplicably need two more templates

* rm get_seconds_hires

* make fwn namespace private for dox

* hide internal fwn from documentation

* fix doc

* rm deprecated euler

* rm __1

tutorial/709_SLIM/main.cpp

@@ -269,7 +269,7 @@ void check_mesh_for_issues(Eigen::MatrixXd& V, Eigen::MatrixXi& F) {
   if (connected_components!=1) {
     cout << "Error! Input has multiple connected components" << endl; exit(1);
   }
-  int euler_char = igl::euler_characteristic(V, F);
+  int euler_char = igl::euler_characteristic(F);
   if (euler_char!=1) 
   {
     cout <<