Ensure elfeed-search-browse-url stays in Elfeed buffer
Ensure elfeed-search-browse-url stays in Elfeed buffer

If some emacs internal browser such as `eww` is invoked by `browse-url`,
the remainder of the function ran in the `eww` buffer which didn't make
sense and didn't visually mark the entry as read.

Fixes #425. Closes #426.

skeeto/elfeed,skeeto/elfeed,emacsmirror/elfeed,emacsmirror/elfeed