fix link for wikipedia SOLID article
Merge pull request #291 from autermann/fix/invalid-link

Fix link for Wikipedia SOLID article
Keep one line nested classes at the top, move multi-line nested classes to own file.
Merge pull request #278 from equivalent/inner_classes

deffinition of small inner classes should be at the bottom of class
Remove a redundant use of %r
grammar and indentation fix for readability
Merge pull request #296 from julio73/patch-1

grammar and indentation fix for readability
Style refactoring on indentation
Merge pull request #298 from julio73/patch-2

Style refactoring on indentation and spacing