Implement line-wrapping in qdiff

Overview
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Many text terminals are limited in width. For legacy reasons, typically a line-width of 80 characters is used with hard line-breaks inserted. In some cases, however, this is not practical -- in particular for documents that represent articles or books (i.e. have a lot of paragraphical text as opposed to short-lined code).

Sample use-case
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Jane is using Bazaar to manage her M.A.Sc. thesis, which she is compositing using the LaTeX typesetting program. Jane is often re-wording sentences, changing paragraphs, and updating equations. For this reason, she uses a single line to represent a single paragraph, and enables word-wrapping (or line-wrapping) in her LaTeX/text editor, since inserting hard line breaks would make updating a paragraph tedious (to keep the line lengths proper) or difficult to read (leave line breaks wherever they were).

Jane wants to review some changes from a commit a few days prior. She opens qdiff to compare the pre- and post-commit versions of particular <chapter>.tex file, however it is very difficult to identify all the changes that occured in a particular paragraph, as in qdiff it is shown on a single, long line of text. She slowly scrolls qdiff over to the right, scanning the paragraph for blocks of highlighted text, but in doing so her eyes become fatigued and she misses a critical change that she should have noticed and reverted.

Recommendation
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Implement line-wrapping in qdiff to make comparing files with long lines easier and more accurate to read by humans.