Preprocessor update

— fix LaTeX compilation error with some expressions (#263)
— fix handling of some special characters in LaTeX
— add “xls_sheet” and “xls_range” to “calib_smoother” (#1695)
— license file update

preprocessor @ e4bdc022

-Subproject commit 4e2538a2a2c141352e6de6dd6538d51854018f70
+Subproject commit e4bdc022a4333d6a96bdd53dcc27840a85ca3e28