Fix issue with copy_plugin.cmd failing with exit code 4.

Add /r switch so xcopy will copy read-only files as well.
Merge pull request #2220 from DanRigby/master

Fix issue with copy_plugin.cmd failing with exit code 4
Rare crash fixed
Disabled UpdateSubmodules for Stash pop/apply (they not change submodules)
Empty brackets for submodules fixed
ProcessSubmoduleStatus fixes
Project dependencies fixed
VS2010 solution removed
TfsInterop.Vs2013 removed from VS2012 solution
Error checking when building installer added
UpdateSubmodules on Fetch fixed
Copyright updated