Do not use pasteboard for yank/delete/pull

Uses the "" register instead
Add [no]pasteboard option to allow optional clipboard usage
Merge branch 'pasteboard'

* pasteboard:
  Add [no]pasteboard option to allow optional clipboard usage
  Do not use pasteboard for yank/delete/pull

Conflicts:
	Documents/Users/FeatureList.md
	XVim/XVimNormalEvaluator.m
Merge commit '0a97b' into refactoring

* commit '0a97b':
  Add [no]pasteboard option to allow optional clipboard usage
  Do not use pasteboard for yank/delete/pull

Conflicts:
	XVim/XVim.h
	XVim/XVim.m
	XVim/XVimNormalEvaluator.m
	XVim/XVimSourceView+Vim.m
	XVim/XVimVisualEvaluator.m
	XVim/XVimYankEvaluator.m
Now pasteboard is not supported. clipboard=unnamed should be used instead