Some fixes for STYLEGUIDE.md

* Use `a` prefix on declared parameter lists... change all samples and mirror under naming
* Use `www` for Wikipedia ... this allows Wikipedia to choose the language based off browser instead of us.
* Miscellaneous sentence structure enhancement.
* Whitespace adjustment

Applies to #262
Merge pull request #263 from Martii/Issue-19StyleGuide

Some fixes for STYLEGUIDE.md