Merge branch 'master' of https://github.com/jreybert/vimagit into next

* 'master' of https://github.com/jreybert/vimagit:
  plugin/magit.vim: add reset mapping in diff context ref #97
  README.md
  plugin/magit.vim: enlarge or shrink hunks fix #97
  doc/vimagit.txt: add vimagit-g:magit_jump_{next,prev}_hunk variable links fix #87
  Add Gitter badge