Simplify left bar tables for all templates

* Un-bold text in the left bar that is not important to let other
  pieces of the UI be more prominent.
* Right-align number values to more easily see the difference in a
  column of numbers.
* Remove top/bottom padding from .well and .table to save vertical
  space.

Review: http://reviews.apache.org/r/12829
Prefer "ng-show" to jQuery accessors

The loading GIF can be shown/hidden based on a scope variable without
involving jQuery (down w/ jQuery).

"#navbar" is never hidden, and so the "show()" call was unneeded.

Review: http://reviews.apache.org/r/12831
Iterate over all offers only once

Offers are first appended to "$scope.offers" while iterating over each
framework, and then "$scope.offers" is iterated to calculate stats. The
stats can instead be calculated at the same time the offers are
appended to "$scope.offers" to save an iteration.

Review: http://reviews.apache.org/r/12832
Removed unneeded mapping of ID -> executor

`framework.executors` and `framework.completed_executors` were arrays
that were converted into maps of ID -> executor, and then the template
called `_.values` to use just the values, i.e. the original executor
arrays, to sort the table.

Stick with the original arrays and save lots of allocation.

Review: http://reviews.apache.org/r/12833
Iterate frameworks successively to save concat

`concat` concatenates two Arrays and returns a new Array. `frameworks`
and `completed_frameworks` can be iterated successively to save
allocation of a new Array that is thrown away after finding the current
framework.

Review: http://reviews.apache.org/r/12834
Replace jQuery with Angular's jQlite in app.js

Angular's jQlite can replace the use cases in app.js, which moves Mesos
a step closer to dropping jQuery completely. No functionality changed.

Review: http://reviews.apache.org/r/12835
Replace popover with copy button on /slaves/:id

This page was still using a Popover for its framework ID rather than
the updated copy button using ZeroClipboard.
Review: http://reviews.apache.org/r/12878