Bundle configuration options that are inferred from the bundle specs
overwrite user provided ones. This used to prevent users from changing
the name of directory where the cloned bundle should go, for instance.
Keep the user provided options with a preference over inferred ones.
1. Fixed some lines which were wider than 78 characters.
2. Added a couple of more borders above all the sub-sections.
3. Moved about part above the TOC, seems unnecessary to have that as its
own section when it's so small. This also look more like a default vim
help file.
4. Changed "NOTE:" into "Note that" because that is more like how it's
used in default vim files.
5. Changed some wording like "the plug-in manager" to "a
plug-in manager".
6. Moved a couple of *tag names* below their headings so it's like that
everywhere in the file.
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.