Add a chart to show number of crash reports over time in a given component/team

[marco-c]

We'd need to gather data from Socorro.

See also https://bugzilla.mozilla.org/show_bug.cgi?id=1277337.

[marco-c]

Instead of going from Socorro -> Component -> Team, we can go Bug -> Socorro (using crash signatures) and Bug -> Component -> Team.

The chart can show the total number of crashes from signatures linked to the bugs belonging to a given team.

It would also be nice to show a list of the top crashers for that team.