Update .gitignore

.gitignore

@@ -2,6 +2,7 @@
 *.vtu
 *.pvd
 *.pvtu
+*.vtk
 
 # ignore ARH files
 *.arh
@@ -14,4 +15,15 @@
 # ignore build directories
 build*/
 install*/
-output*/
\ No newline at end of file
+output*/
+
+# ignore CMake files
+CMakeCache.txt
+CMakeFiles
+CMakeScripts
+Testing
+Makefile
+cmake_install.cmake
+install_manifest.txt
+compile_commands.json
+CTestTestfile.cmake