Improve README instructions & presentation

jorgebucaran commented 5 years ago

This PR improves the README presentation, indentation, and instructions.

Replaces ~~fisherman~~ with Fisher
Replaces `bash with `fish
Replaces "plugin" with "package"
Adds License section with a link to the LICENSE file
Updates .travis.yml to use Fisher (although it's still broken because of https://github.com/jorgebucaran/fisher/issues/513)
Adds a link to https://fishshell.com in dependencies section

@franciscolourenco The only thing I can't include to this PR is changing your GitHub repository tags. Could you change:

Cheers.

franciscolourenco commented 5 years ago

I've edited the tags.

jorgebucaran commented 5 years ago

Thank you!

jorgebucaran commented 5 years ago

@franciscolourenco The repository description still says "plugin". Could you update that too for consistency?

franciscolourenco commented 5 years ago

Done, and thank you!

franciscolourenco / done