Fix crash while navigating the stack frame
Merge pull request #581 from mohitsharma0690/fix_crash

Fix crash while navigating up/down in the stack frame
Add :undo support. Fix #618
Merge branch 'develop' of github.com:JugglerShu/XVim into develop

* 'develop' of github.com:JugglerShu/XVim:
  Fix crash while navigating the stack frame
Adding Xcode 6 GM seed compatibility UUID
Merge branch 'patch-1' of https://github.com/martinblech/XVim into develop

* 'patch-1' of https://github.com/martinblech/XVim:
  Adding Xcode 6 GM seed compatibility UUID