Scrolling of crammed widgets

[mocdaniel]

7 lines of CSS in application.scss to allow the scrolling of widgets when they are crammed with entries. Especially useful for List and Simplelist widgets.

The changes do not affect the appearance of Dashing Icinga2. The scroll bars get pushed out of rendered areas by CSS for every browser and a widget's title and moreInfo sections stay where they are while scrolling content.

The functionality is enabled on a per-widget basis by adding the class=scrollable tag within their declarations in the respective dashboard.erb files.

[mocdaniel]

If requested for matters of consistency of configuration, I can also add a ruby method to config.ru which reads from config/icinga2.json and writes the class-declaration to the widgets when being called. (similar to the method which allows to get the time zone) from #94

[dnsmichi]

I don't mind making this the default. I prefer not to cause confusion with too many config options controlling the behaviour. A config setting always is last resort in contrast to pushing a wanted behaviour. Users who don't like it are still encouraged to edit the dashboard being only an example.

[dnsmichi]

Thanks for the patch 👍