Added README.md for Jenkins and fixed the Makefile.

Review: https://reviews.apache.org/r/12938
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
Fixed MesosNativeLibrary to use MESOS_NATIVE_LIBRARY environment
variable instead of system property.

From: Shingo Omura <everpeace@gmail.com>

Review: https://reviews.apache.org/r/12975
Style /browse to distinguish folders

* Add small folder icons to the left of folders to distinguish them
  from other files.
* Right align Size, Nlink, and mtime columns.
* Remove 'name' title since it is apparent
* Order files first by file type, i.e. folder or not folder, and then
  by name.

Review: http://reviews.apache.org/r/12887
Compute framework stats in one iteration

Rather than iterate over 'frameworks' and 'completed_frameworks' once
to update the slave mappings and a second time to calculate stats for
the frameworks, move that work into a single loop.

This also removes a 'concat' call that was creating a temporary Array
used to calculate stats once and then thrown away.

Review: http://reviews.apache.org/r/12880
Remove 'ui-if' direction in favor of 'ng-show'

Angular provides 'ng-show' to hide elements when not needed. They are
rendered in the DOM unlike with 'ui-if', but using native Angular
prevents needing outside code or dependencies for a directive used in
only one template.

Review: http://reviews.apache.org/r/12888/
Changed the SIGTERM handler to not dump a stacktrace.

Review: https://reviews.apache.org/r/13028
Removed unnecessary sleeping from the test executors.

Review: https://reviews.apache.org/r/12781
Search frameworks & executors successively to save concat

Array.concat creates a new Array, which in this case is used once to
find frameworks and executors and then thrown away. Instead the Arrays
can be searched successively in place without allocating more memory.

Review: http://reviews.apache.org/r/13002
Remove HTML5 shim for <IE9

IE8 and below are officially no longer supported. The shim only loaded
in IE8 and below, and so it can be removed without affecting supported
browsers.

Review: http://reviews.apache.org/r/13005