Update .travis.yml

Allow external
added SimpleReadOnlyWidget
Merge branch 'develop' of github.com:allegro/ralph into 403view
'' as readonly value for SimpleReadOnlyWidget
Merge pull request #943 from xliiv/ro-widget

readonly-widget
better shares detection + tests fix
fix
fix
Merge pull request #944 from andrzej-jankowski/develop

[Scan] disk shares detection - improvement
Documentation for 2.0 release
Badges and others
Tests fixed
Merge pull request #946 from vi4m/docs_20

Docs 20
added assets and scrooge docs
Fix #2
Changed Readme title
Merge pull request #947 from allegro/feature/added-scrooge-and-assets-docs

added assets and scrooge docs
Collecting events that can possibly affect a CI
Fixed error, where importing PIL warned about permission denied
Explanation added