Improved commands section of help file
Updating typos per @ujihisa's comments
Merge pull request #248 from csexton/doc-commands

Improved commands section of help file
- Added unite#set_substitute_pattern() warnings.
- Fixed unite#custom#profile().
- Fixed subst.
- Optimized for Windows.
- Fixed error in Linux.
Updating README

I thought it would be fun to add a bit of a logo for Unite. I wasn't
sure what the best mascot for the plugin would be, but figured it would
be hard to beat a dragon. I went with a dragon, one who's body is in the
shape of a "U". I thought it came out pretty well, especially for a quick
effort.

Added an animated gif screen cast of some basic unite functionality.
This seemed like a better way to get the basic concepts of the plugin
across quickly.

Rearranged a bit of the content to group resources together in one spot.
Reverting gif to an image tag

Seems the animation doesn't play with the markdown style tags
Merge pull request #249 from csexton/readme

Updating README
- Added unite#custom#substitute() for backward compatibility.
- Added tab option.
- do BufWinEnter autocmd in open action.
Updated example vimrc settings
Merge pull request #250 from csexton/doc-examples

Updated example vimrc settings
- Improved documentation.
- Fixed for compatibility in rec sources.
fix missing <C-u>s (refs #250)
- Fixed unite#custom#profile() error.