Update Markdown files

- Fix indentation and hard wrapping in the files.

- Add a proper Unicode copyright symbol to license.markdown.

- Update year in license.markdown.

- Add a mention about OS X support to readme.markdown.

- Update prerequisites in readme.markdown.

- Fix Travis link in readme.markdown.
Update ignore lists

- Remove *.fuse_hidden* from .gitignore.

- Have Sublime Text ignore everything that .gitignore does.
Move from lowerCamelCase to snake_case
Use smart pointers in the window class