Add setting to control which files ignore changes in space in diff view.

Review Request #173 — Created Oct. 23, 2007 and submitted


Review Board SVN (deprecated)


Simple change to allow you to configure which files ignore whitespace-only changes based on filename.
Behavior is unchanged by default.  Did some testing with DIFF_INCLUDE_SPACE_PATTERNS set to ['*'] which makes space significant for all files.  Also tested sets such as ['*.py', '*.pyx', '*.pxd', '*.pxi'].