Do not use pasteboard for yank/delete/pull

Uses the "" register instead
Add [no]pasteboard option to allow optional clipboard usage
Add vim proper .swp files to .gitignore
README: some corrections & rephrasing
More README pickiness
Merge pull request #323 from claybridges/clay-readme

Mostly corrections or rewordings of README.md
% register implementation
Implement jump back related to issue #267 feature request
correct jump back motion
correct typo
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 pull request #326 from pebble8888/jumpback_patch

Implement jump back related to issue #267 feature request
Merge branch 'percent_register' of https://github.com/pebble8888/XVim

* 'percent_register' of https://github.com/pebble8888/XVim:
  correct typo
  % register implementation

Conflicts:
	XVim/XVim.m
Merge remote-tracking branch 'upstream/master'