Readonly views work in database tab.

[durran]

Before the database tab would not display anything if the database had readonly views. This was due to 2 reasons:

1. The collStats command could not be executed against the system.views namespace when readonly views exist, because it is a system namespace.
2. The collStats command failed when executing against a readonly view directly.

The mongodb-data-service 2.4.0 release filters these out instead of erroring, which is updated in this pull request. We also now format the readonly views in the table to display - instead of all zeros for values.

This also now indicates in the collection view if the collection is a readonly view with a lock next to the name:

[imlucas]

Lgtm once remaining test failures resolved. Lock icon doesn't map quite right. Implies I can't access the collection because of permissions instead of the intended "this is a read only view". The fa-eye would be more traditional here.