ab: add git ignore

.gitignore

+# file types
+*.pdf
+._*
+
+*.aux
+*.bbl
+*.blg
+*.log
+*.out
+*.lof
+*.lot
+*.synctex.gz
+*.toc
+*.pyc
+
+# folders
+examples/read_data/Zwick_data/results
+examples/read_data/STL_data/results
+examples/read_data/STL_data/processed_data
+examples/create_graphic/results
+examples/image_analysis/field_over_picture/results
+examples/curve_analysis/trapezoidal_integration/results
+examples/image_analysis/find_contour_from_an_image/results
+examples/mesh/vtk_to_inp/results
+examples/threshold_data/results
+examples/indentation_analysis/anton-paar_indentation/processed_data
+