Removing the osx/bulk.md file since the remaining content is Linux/Unix and not specific OS X. Added collapse/expand script to navigation.md page.
Merge pull request #41 from WebBreacher/osx

Removing the osx/bulk.md file since the remaining content is Linux/Unix ...
Adding netcat content and also a navigation item for all the *cats (socat, ncat, and netcat)
Merge pull request #42 from WebBreacher/cats

Adding netcat content and also a navigation item for all the *cats (soca...