Update docs badge in README

Update the URL of the docs badge to include it from inch-ci.org instead of inch-pages.github.io (the former being the successor of the Inch Pages project).

[ci skip]
Merge pull request #1575 from rrrene/patch-4

Update inch-ci docs badge in README
Fix the errors happening on Travis
Converted some be_trues and be_falses
 Replace drop_attached_file with remove_attachment
 as the former is deprecated and throws a warning.