Fixes by c24b.
FIX by c24b
FIX: errors in exo 45.
 fix error drafts
Nightly update.
add 260
 update readme 260
fix 102
fix 102 tjrs
fix 250
fix 240
461
461
fic know 461
New exercice from c24b :-))))
help for 250
Caesar: More details.
FIX: Be clear about the difference between usage and input error.
Merge remote-tracking branch 'upstream/master'