Changelog

TODO
- savoir si lorsque erreur il faut enlever ou pas l'argument en erreur de la stack
  - normalement non, c'est bon?

Compatibility is broken on these points
- `<< <<` doesn't input as `<< << >> >>` but as `<< << >>`
- `1 2+` not allowed anymore, keep `1 2 +`
  - this corrects bad behaviors like `3b114` giving `3b11` and `4`
- complexes are written in the form `(1,2)` instead of `(1, 2)` (space is removed)
- removed useless 'unti', 'repea', 'whil' (existing for HP28S compatibility)
- removed 'sqr' function, please use 'sq' instead (existing for HP28S compatibility)
- syntax error code is now 12 instead of 11
- `test` command can also take a symbol as a parameter ; if the symbol contains a valid
- à l'affichage le préfixe des chiffres en base 2 est 0b et pas 2b (la saisie 2bxxx est toutefois permise)
- à l'affichage le préfixe des chiffres en base 16 est 0x et pas 16b (la saisie 16bxxx est toutefois permise)
- à l'affichage les chiffres en base 10 pas de préfixe 10b (la saisie 10bxxx est toutefois permise)
- `mant` and `xpon` now give binary significand and exponent, as it is the norm (see frexp in math.h, cmath for example)
- `dupn`, `roll`, `rolld` are not leaving anymore their argument in front of the stack in case of error
- entering the sign after the base (ex: 0x-1e2) is allowed

New
- `«` and `»` are now valid as program delimiters. `<<` and `>>` are still valid
- enhanced code quality and memory usage checks
- added `norm` as a synonym of `abs`

cas de tests à ajouter:
ab Xb 1b
ax 0X 3X
0x12pa1