Added missing apostrophe to the contraction "it's"
Attempting to make the 'Events' section more clear.

Minor language tweaks and grammar corrections.
Some language tweaks to the Router and Sync sections.
Fixed indentation; added missing semi-colon
Fixed Mixin/Inheritance example indentation to be 2 spaces.
First bit of time spent refactoring the RequireJS section, adding, deleting and moving bits around
Fix typo in comment url.
Fix code block markup.
minor type in comment line 1616
Add missing 'of' word.
Placeholder image extension is .png (not .gif).
Minor cody tidy up (white space, added var, redeclaration of PanelAdvanced).
Merge branch 'gh-pages' of github.com:addyosmani/backbone-fundamentals into gh-pages
fix RequrieJS typo
fix indenting in code example
working on RJS configuration section
add section on config and shims
Fix typo in comment url.
extended/merged MVC theory part into the book
merge and restructuring of the intro section with simple js mvc implementation - partialy done