Fix wiki links

Github's new way of handling relative links broke some of the
links in the readme file.

Seems to have broken with GitHub's relative link change https://github.com/blog/1395-relative-links-in-markup-files

**V**imb**undle** no longer rendering properly...

Fixes #217

Closes #206: alias `BundleUpdate` to `BundleInstall!`

inspired by
https://github.com/gmarik/vundle/pull/228 and
https://github.com/gmarik/vundle/pull/172

Vim patch #445 changed shell escaping and introduced incompatabilities for vundle.
Now vundle only escapes joined commands with double quotes on windows when shellxquote is not set to '('.
This workaround closes https://github.com/gmarik/vundle/issues/146 - the mentioned workaround
is no longer needed, but it does not break a vim configurations which contains "set shellxquote=".

DRY shell escaping and modified (hopefully) all relevant places.

'BundleUpdate' is a more intuitive and explicit command, whereas 'BundleInstall!' isn't.

- causes #203

This reverts commit 1e140c9f6b.

- link to contributors

- not all versions of vim 7.2 support the extra argument for glob*(),
  only those compiled with patch 51

- make it append only (instead both append + prepend)
- which draws *_rm_a and *_add_a useless as &rtp order gets preserved
- benefits: simpler, faster, less code

Fix wget/win32 codepath for script searching.

The codepath does not appear to have been tested; mv on Win32 is move,
and substitute has 4 arguments instead of 3.

Vundle can manage Vundle, when it cloned as git submodule

When vundle installed as git submodule, git create file '.git' instead of
directory '.git'.

And vundle cannot update by self :(

With just `git clone`, submodules are not grabbed. This is an issue for
certain plugins, such as 'kevinw/pyflakes-vim' that requires a pyflakes
submodule

Changelog does not work on Windows

- 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

Create Changelog when performing BundleInstall!

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.

Link to vimified conf in README

Thanks!

- closes #141

- also work in batches

- having it as a function makes it slower

change setup url to use HTTPS instead HTTP