Fix: inadvertent scroll when loading the instructor's extensions tab

(The div with id "view-extensions" conflicts with the tab JS which sets location.hash to "view-x" in order to track the current tab)
Bok-Choy Video Transcript Tests
path_to_location now returns 404 on orphaned items. Resolves LMS-9661.
Add placeholders for text input on Extensions dash feature
Check for npm registry and set it if necessary.

If paver is being run by a user that is not the same as the user
that installed npm on the guest machine, then paver install_prereqs fails
with the following error:

  ---> pavelib.prereqs.install_node_prereqs
  npm config set registry http://registry.npmjs.org/
  npm ERR! Error: EPERM, chown '/home/jenkins/.npmrc'
  npm ERR!  { [Error: EPERM, chown '/home/jenkins/.npmrc'] errno: 50, code: 'EPERM', path: '/home/jenkins/.npmrc' }
  npm ERR!
  npm ERR! Please try running this command again as root/Administrator.

  npm ERR! System Linux 3.2.0-23-generic
  npm ERR! command "/usr/bin/node" "/usr/bin/npm" "config" "set" "registry" "http://registry.npmjs.org/"
  npm ERR! cwd /home/jenkins/shallow-clone
  npm ERR! node -v v0.10.30
  npm ERR! npm -v 1.4.21
  npm ERR! path /home/jenkins/.npmrc
  npm ERR! code EPERM
  npm ERR! errno 50
  npm ERR! stack Error: EPERM, chown '/home/jenkins/.npmrc'
  npm ERR!
  npm ERR! Additional logging details can be found in:
  npm ERR!     /home/jenkins/shallow-clone/npm-debug.log
  npm ERR! not ok code 0

  Captured Task Output:
  ---------------------

  ---> pavelib.prereqs.install_prereqs
  ---> pavelib.prereqs.install_ruby_prereqs
  ---> pavelib.prereqs.install_node_prereqs
  npm config set registry http://registry.npmjs.org/

  Build failed running pavelib.prereqs.install_prereqs: Subprocess return code: 50

This change is a workaround. It will first see if the value is set. In the case
that is it not set, it will attempt to set it. (It will then fail; however,
re-running the task will subsequently be successful.)
Merge pull request #4905 from bradenmacdonald/fix-idde-ui

Fix: inadvertent scroll when loading the instructor's extensions tab
Merge pull request #4828 from edx/benp/workaround-npm-error

Paver: Check for the npm registry and set it if necessary.
Merge pull request #4896 from Kelketek/fix_path_to_location

path_to_location now returns 404 on orphaned items. Resolves LMS-9661.
Studio: revising %cont-text-sr Sass placeholder based on modern browser support
Studio: breaking longer user/id-based strings on unit and container views

STUD-2113
adding tests for country list in different languages

updating the version for django_countries
Merge pull request #4911 from edx/sarina/a11y-extensions

Add placeholders for text input on Extensions dash feature
Merge pull request #4902 from edx/mvo/adding_tests_for_country_list

adding tests for country list in different languages
Friendly error if invalid student identifier is entered for due date extension
Merge pull request #4906 from bradenmacdonald/fix-idde-invalid-student

Friendly error if invalid student is entered for due date extension
Merge pull request #4916 from edx/talbs/studio-fix-unitsidebar

Studio: FIX - Unit/Container Sidebar Content Wrapping
Merge pull request #4859 from edx/ammar/bok-choy-video-transcript-tests

Bok-Choy Video Transcript Tests Batch1
STUD-1911, STUD-1932: Publish sections, subsections and units from course outline.