Move Debian alternatives entry up.

Move the Debian alternatives entry up so it's below and grouped with
"no such file or directory" since it's an alternate solution to symlinking.
add Slackware install method
:arrow_up: apm@0.111.1
Prepare 0.154
:arrow_up: language-less@0.20
:arrow_up: language-python@0.25
Merge pull request #4406 from atom/mb-editor-text-content

Allow setting editor text content in HTML
:pencil: ability to pass DOM elements to atom.commands.add
:arrow_up: git-diff@0.45
:arrow_up: find-and-replace@0.150
Merge pull request #4405 from ryanpcmcquen/patch-1

:penguin: add Slackware install method
Merge pull request #4393 from envygeeks/patch-1

Move Debian alternatives entry up.
Fix line numbers in coffeescript stack traces for error hooks