Fix various SVN escaping issues in arc patch

Summary: Followup to D4703. When we give paths to `svn`, we need to escape them if they contain an `@`.

Test Plan:
Created a patch full of modifications to files with `@` in their names, and applied it:

  $ arc patch --diff 192
  A         A@2xcopy2
  A         A@2xcopy
  D         A@2x
   OKAY  Successfully applied patch to the working copy.

Reviewers: chad, mbishopim3

Reviewed By: chad

CC: aran

Differential Revision: https://secure.phabricator.com/D4977
Fix "none" in SVN XML summary

Summary: The `svn diff --xml --summarize` command reports a bunch of item statuses, which may include "none" if you make property changes to a directory (this is fairly rare).

Test Plan: Created property changes, saw "none" status.

Reviewers: chad, mbishopim3

Reviewed By: chad

CC: aran

Differential Revision: https://secure.phabricator.com/D4978
Arc diff tries to upload files it knows about using a content hash rather than transfering data.

Summary:
Arc diff will hash file data and try to upload the file using upload by hash rather than transferring data. If it is unable, it defaults to its normal behavior

Attempts to upload file by hash, use regular upload method otherwise

Test Plan: Figure out how to arc diff to my local install and look at the behavior

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin, mehrapulkit

Differential Revision: https://secure.phabricator.com/D4968
Fix another SVN issue with "@" files

Summary: This chunk of code is kind of iffy and not really correct, but make it not fail, at least.

Test Plan:
  - Added a file named `swamp@2x.jpg` to a working copy.
  - Used `svn propedit svn:mime-type swamp@2x.jpg@` to incorrectly set its mime type to `text/plain`.
  - Ran `arc diff`.
  - Saw `arc diff` "correctly" change its mime-type to a binary mime type. This isn't really correct, but doing it successfully is better than throwing an exception.

Reviewers: mbishopim3, chad

Reviewed By: mbishopim3

CC: aran

Differential Revision: https://secure.phabricator.com/D4998
Parse property change diffs generated with old SVN (prior to 1.5)

Summary:
Fixes T2565. SVN from before June 2008 generates different looking property changes.

See http://subversion.tigris.org/issues/show_bug.cgi?id=3019 for the change.

Test Plan: Added a unit test derived from the report in T2565, made it pass.

Reviewers: chad, vrana

Reviewed By: chad

CC: aran

Maniphest Tasks: T2565

Differential Revision: https://secure.phabricator.com/D5009
Merge branch 'master' of http://github.com/facebook/arcanist