Fix tracking of line numbers in IL code (error messages were previously indicating incorrect line number).

Fix bug in datatype narrowing algorithm affecting IL code.

Set the symbol->token member in symbolic_variables_c objects.

Debugging helper class: print value of tokens in debugging output.

Fix bug: allow global variables of type DT (initial values for DT are not const!)

Add comment stating how to enable debug option in flex.

merge

Print error message when FB/Struct initial value contains other strcuts/FB/arrays (not yet supported by C code generator).

Do datatype checking of initial values for structures and FBs, and print error messages when compiling erroneuos source code.

fix bug in symbol_c::find_element()

Acceept structure_element_declaration_c symbol as a possible (non base type) data type

Add token references in structure_element_declaration_c

Add token reference to all symbol_c, and add list_c::find_element()

remove debug code left in by mistake in previous commit