First draft of session 3
Changes to fix formatting
Snippet sanitization
typo
Fix examples
Add object-orientation interlude
Add doc link for OS
Add merge neighbouring loops refactoring
Add comment about lint
Add temporary variable refactoring
Merge pull request #5 from UCL/session3

Session 3: Code construction
Session 4
linting and code checks
Design patterns added to session04
Add static methods section
Use code fragments to check that syntax is right
Exercises
Further syntax fixes
linting
Merge pull request #10 from UCL/session4b

Session 4