Disabled external gits

cs440-acg/ext/eigen/doc/snippets/MatrixBase_start_int.cpp

@@ -0,0 +1,5 @@
+RowVector4i v = RowVector4i::Random();
+cout << "Here is the vector v:" << endl << v << endl;
+cout << "Here is v.head(2):" << endl << v.head(2) << endl;
+v.head(2).setZero();
+cout << "Now the vector v is:" << endl << v << endl;