Allow changing default diff parameters

We use git for version control. Sometimes with many small changes close together, the Crucible diff shows many more changes than git diff does, occasionally showing the entire file as being different. This makes it difficult to review.

I am asking for a way to change the default Crucible diff parameters, for example, number of context lines considered before highlighting a change, the diff algorithm, end-of-line characters, etc. so smaller diffs are produced.