Add symlink_dotfiles.sh

This script is used to symlink the necessary dotfiles to the `$HOME`
directory. Files are specified explicitly to be included. Install now
only depends on `git` and `bash`.

This script is largely based on Zach Holman's dotfiles bootstrap script.
Update VIM settings

- Fix python indent inside parens
- Remove `html` and `css` FT settings
- cleanup vimrc
- add plugin "indent guide"
Update / Clean up / Minor edits