Fix windows annotations

[nh2]

Windows doesn't allow other programs to read files created with tempfile.NamedTemporaryFile(delete=True). That's why we get something like:

Exception in thread Thread-173:
Traceback (most recent call last):
  File ".\threading.py", line 532, in __bootstrap_inner
  File ".\git.py", line 96, in run
  File ".\subprocess.py", line 701, in communicate
  File ".\subprocess.py", line 911, in _communicate
IOError: [Errno 32] Broken pipe

Also, diff is usually not installed on windows. One of these commits tells the user about this.

Side note: It would be cool if the checks for the existence of external programs could be done in some initialisation part of the plugin, like in the detection phase of SublimeLinter.

[sheldon]

Thanks for the patch, I agree about the detection too it would be nice. If there's any other windows users that can confirm a test of this as working I'll get it merged up.

[sheldon]

@nh2 I did a little reading through this and it seems ok to me. the intention is to throw a nicer error on not being able to run annotations via diff right? if you say you've done a thorough test I'll get it merged up anyway, as it seems we don't have anyone testing separately. can always revert if there's any major problems.

[nh2]

the intention is to throw a nicer error on not being able to run annotations via diff right?

Yes.

I tested it on a Windows 7 machine and would prefer if others could confirm that it works for them, but if we don't have anyone trying it, we should probably merge it and see if people complain.

[hex]

I tried this fix on Windows 7, but the annotations don't appear. I got rid of the erros, but still no live annotations.

[Kos]

I confirm that this fix has worked for me on Windows 7 64bit.