- add /d switch to cd command to perform drive change
- enclose joined commands with quotes

Instead checking for specific text in the output of the git commands, determine
the status of the bundle by comparing the sha of HEAD before and after the
git pull command.

- as before Helptags returned 'updated'

- addresses #162 issues

If no errors exist, the status-line will inform users how to view the
Changelog after BundleUpdate! is completed.

Instead of creating a vundle_update tag to compare changes between update
and HEAD we now use the output from `git pull` to get initial/updated shas.

Distinction between `new` and `updated` simplifies the process
of adding a bundle to the updated_bundle list.

If the Bundle is hosted on GitHub include link to compare the commit range
visually on GitHub.

Keeps track of the current commit with a vundle_update tag before
perfoming an update and adds all commits pulled in the update to a
Changelog accessible via pressing 'u' after BundleInstall! completes.

- also work in batches

- having it as a function makes it slower

- as `http` one just redirects to `https` on GitHub

- use `let g:vundle_default_git_proto = 'git'` to set default protocol
to build URIs to clone from

- "transcient bundle" - a bundle installed with :BundleInstall or interactively
  without being declared in .vimrc

- treat them the as if they were configured
- so everything works the same

- ie before this change helptags weren't generated automatically
  with `BundleInstall bundle` or with interactive mode

- it changes the way `:BundleClean` works, since it removes directories
  that aren't bundles
- FIX: `:source .vimrc` to let `:BundleClean` remove transcient bundles

- closes #99

- closes #64

- closes #104

- closes #110

Also save/restore input so potential mappings aren't broken.

Prevents the user from having to type a space before the search term.

- closes #80

- use `redraw` instead `redraw!`
- closes #90

- to avoid accidental removal