Lecture 05
Fix small typos
Merge pull request #35 from NikolayGenov/05-fix-typos

Fix small typos
Fix typos and examples in lecture 04
Merge pull request #34 from dkeranov/04-fix-examples

Fix typos and examples in lecture 04
Fix a typo in lecture 05
Merge pull request #36 from mdimitrova/05-fix-typo

Fix а typo in lecture 05
Add 2 new slides about overloading of operators

Listed all the operators, which can be redefined. Used information from the following sources:
http://ruby.about.com/od/oo/ss/Overloading-Operators.htm
http://phrogz.net/programmingruby/language.html#table_18.4

Also corrected the outdated list of instance methods of Enumerable (lazy was missing).
Merge pull request #38 from yasen23/new-slides-05

Add 2 new slides about overloading of operators
Make two links clickable
Merge pull request #37 from EmanuelaMollova/01-fix-links

Make two links clickable
Range of the swipe area extended to 100% height
Merge pull request #39 from georgieff/lectures-swipe-area-range

Lectures swipe area range
Add lecture 06
Fix some typos in lecture 06
Merge pull request #41 from mdimitrova/06-fix-typos

Fix some typos in lecture 06
Fix a syntax error in slide 41
Merge pull request #44 from mignev/05-fix-typo

Fix a syntax error in slide 41
Fix various minor typos/mistakes

Conflicts:
	lectures/06-classes-namespaces-inheritance.slim
Clarify slide about global namespace access