BUG: Updating DTIProcess from r213 to r214

BUG: Searching for SVN and passing its path in the Superbuild process to compile as a Slicer extension. The value of this variable seems to be required:
http://slicer.cdash.org/viewBuildError.php?buildid=192440

http://www.nitrc.org/plugins/scmsvn/viewcvs.php?view=rev&root=dtiprocess&revision=214
Merge pull request #586 from fbudin69500/update-DTIProcess

BUG: Updating DTIProcess from r213 to r214