Add swoop.el

Hi, could you add this repository?
https://github.com/ShingoFukuyama/emacs-swoop

This similar to helm-swoop, but works without helm.
I know some people don't like helm...

Here is several differences.
* Stick to the nearest line even after update lines
* Utilize PCRE like regexp
* Utilize migemo (Japanese words search command) search
* Real time edit like occur edit

Thank you.