Adding styles to fix issue BLD-221.

If you make the window smaller, and keep reducing it's size, at some
point the controls will not fit, and some will be bumped to the next row.
When the widnow is resized below the width 1024, extra styling rules
will kick in to fix this issue. The word "Speed" from the speeds control
will be temporarirly hidden.
Merge pull request #822 from edx/valera/fix_controls_stack_2_rows

Adding styles to fix issue BLD-221.
Add event tracking with configurable backends
Monitor event tracking time by backend using statsd
Use datetime objects in time field in event tracking
Merge pull request #797 from rocha/track-backend-configuration

Add event tracking with configurable backends