Add new file for A6 (cello double string)
Merge branch 'master' of https://github.com/MTG/sms-tools
fixed typo in lecture slide
added lectures 9
small typo
Fix typo causing error when incorrect param entered.

When entering an incorrect N value (i.e. not a power of two),
the code fails because the exception has been declared of a typo.
Merge pull request #21 from tychobrailleur/master

Fix typo causing error when incorrect param entered.
Programming assignments 1-4
Add programming assignment 6
Merge branch 'master' of https://github.com/marspeople/sms-tools