Remove all .DS_Store files in project

There were six .DS_Store files in the project directory. These were
generated by the OSX operating system and shouln't be versioned.
Adds a basic gitignore

For now ignoring .DS_Store files to make sure they don't get
reintroduced into the project.
Remove xcuserdata and add rules to gitignore

In the project, there are two places where user specific configuration
was being stored. This makes collaborative editing difficult because
those configuration files will change from user to user even if they
haven't changed any actual code. For this reason, its a great idea to
add them to remove them and add them to the .gitignore file to make sure
they don't get versioned in the future.
Merge pull request #1 from cknadler/master

Removes generated files and adds basic .gitignore