LEXICAL MODULE AND MAKEFILE

1) setup Eclipse project on git
2) setup .gitignore of SOL (includes *.o, *.so, bin/ and flex output).
Bison output is not handled yet.
3) generates Makefile (all the src files must be put inside a directory
in src to better manage the different SOL modules) The makefile can't
compile bison for now. We must add also a check-prerequisites target
rule to ensure flex and yacc are corretly installed on the system
4) create lexical.lex for the lexical analysis.
5) lexical-definition (Lamperti's def.h) is coded.
6) adds Lamperti's files inside "lamperti-files" directory
7) adds "list of lexical tokens" files which holds a list of the entire
tokens used by SOL.