Fix location tracking bugs (i) cursor was not initialized with input file name, ...

Fix location tracking bugs (i) cursor was not initialized with input file name, (ii) id_loc and other places were corrupted by taking a reference to y_tab.yylloc rather than a copy, (iii) lex_yy.scanner_cursor was not put back when putting back text in state SC_AFTER_IDENTIFIER, (iv) line and column should be 1-based