Backup
Fix bugs about syntax `let'.
Fix a bug

Do not eat the second left parenthese when reading syntax `define'.
Remove the use of `readList' in `read_s_with'.
Remove the use of all `readList'.
Lost of modifications...
Remove thress useless functions in `reader.c'
Re-define a syntax for reading vector literal.
Change the type of fields in S_AT and T_REST.
Replace the `eat_char' by `eat_token'.
Re-define the syntax type of reading hash-table.
Define a new syntax type for wrapping object_t *.
Wraps the INTEGER and REAL by means of S_VALUE.
Use the `char *' instead of `Object' used as SYMBOL.
Remove the use of `token2syntax'.
Define and use the S_ID instead of using SYMBOL.
Remove the useless `T_BEGIN' and rename some type of fields.
Change a part of usage of `object_t *' to `syntax_t *'.
Remove two useless functions in file `compiler.c'
Rename the value of enum Type on syntax.