title: Modifying Xcode syntax highlighting to gray-out NSAssert lines
body: <p>I want to modify Xcode syntax highlighting.  Namely, I do a lot of 'NSAsserts', which I find visually distracting, and so I would like lines starting with 'NSAssert' to be a light gray.  This way, I can focus upon my code logic instead of having to cognitively filter-out the NSAssert lines.</p>