Rewriting README and setting default folder/file types

I hope I haven't rewritten too much, maybe most of the changes were rather for my own convenience, yet I hope they are still of some use. The main changes I've done are:

1. Changed `README` file to Markdown.

2. Added `DOTminion` configuration file.

3. Changed all default directories and files to the same locations.

4. Clearly distinguished command line and VIM plugin install.

5. Added instruction for using `minion` with `fish`.

6. Added questions to `TODO`.

I also changed the GitHub user to mine, montauk, so I could test it. I figure it would have to be changed back.