Major updates to resolution code from runs.

* Augment MediaWiki conflict resolution with correct version for
  end of line
* Add prepareMerge to application for pre-merge resolution
  helpers (mostly for line-ending problems)
* Fix MediaWiki resolveConflicts parsing of ls-files output,
  and another unrelated bug
* Add space between logging and summary outputs
* Move backup back to correct location, and perform size calculation
  twice
* UpgradeVerificationFailure gets useful output
* /dev/shm/wizard gets chmod'ed 0777
* Fix resolution algorithm to handle each conflict block individually.
  Test cases augmented accordingly.

Signed-off-by: Edward Z. Yang <ezyang@mit.edu>